CBIC invites public comments on proposed Alternate Mechanism for amendment of tax liability and input tax credit in GST returns; Proposed changes to take effect from the April 2027 return period; consultation open on MyGov till Nov 30, 2026

The Central Board of Indirect Taxes & Customs (CBIC), Ministry of Finance, has Invited comments on November 01, 2026 from citizens, taxpayers, tax practitioners, industry associations and other stakeholders on a proposed “Alternate Mechanism for making amendment in liability and input tax credit (ITC) in GST returns”. The proposal was recommended by the GST Council at its 57th meeting on 8 October 2026.

Under the current system, tax liability in FORM GSTR-3B is auto-populated from FORM GSTR-1, and ITC is auto-populated from FORM GSTR-2B. Taxpayers can still manually edit these values before filing. Such edits create mismatches between liability in GSTR-1 and tax paid in GSTR-3B, and between ITC in GSTR-2B and ITC claimed in GSTR-3B. These mismatches lead to demand notices and system-generated intimations.

Several portal facilities were introduced to reduce mismatches: GSTR-1A, the Invoice Management System (IMS), the Electronic Credit Reversal and Re-claimed Statement, and the RCM Liability/ITC Statement. Apart from GSTR-1A, none of these were notified in the CGST Rules, and many taxpayers continued to edit GSTR-3B manually. The Council therefore recommended:

• All corrections of liability should be made through GSTR-1, GSTR-1A or IFF, not in GSTR-3B directly.
• All ITC management should be done through:
  • IMS
  • the Electronic Credit Reversal and Reclaim Statement (FORM GST PMT-02A)
  • the Electronic Statement of RCM tax paid and ITC claimed (FORM GST PMT-02B)
  • FORM GST PMT-04
  • the new FORM GST PMT-10

The mechanism is proposed to apply from the April 2027 return period. The consultation pack has three parts:

• Annexure A: amendments to the CGST Rules, 2017
• Annexure B: amendments to forms GSTR-1, GSTR-1A, GSTR-2B, GSTR-3B, PMT-02A, PMT-02B, PMT-04, PMT-10 and DRC-03
• Annexure C: a draft circular on correct ITC reporting in GSTR-3B

The consultation runs from 1 November 2026 to 30 November 2026 on MyGov. Suggestions for an area cannot be edited once submitted.

Note: In the consultation document, the proposed amendments to the CGST Rules, 2017 (Annexure A) and to the CGST Forms (Annexure B) are highlighted in red. The points below describe each form as proposed and the changes identified in the consultation note.

2. FORM GSTR-1 (Statement of Outward Supplies) – Rule 59(1)

Previous difficulties

• Credit notes, debit notes, advances received and advances adjusted were not tagged by the nature of the underlying supply (regular, section 9(5), zero-rated, etc.). As a result, they could auto-populate in the wrong GSTR-3B table, usually the taxable outward supplies table, and taxpayers had to correct them manually.
• The format did not let suppliers reconcile supplies made through e-commerce operators (ECOs) with the details the ECOs report in FORM GSTR-8.

Proposed changes and simplifications

• Table 4 (B2B supplies) is split more finely:
  • 4A: regular supplies to registered persons. Excludes reverse charge supplies, section 9(5) ECO supplies, supplies by SEZ on a bill of entry, and supplies through ECOs attracting TCS under section 52.
  • 4B: supplies attracting reverse charge. Includes reverse charge supplies to SEZ for non-authorised operations, which go here and not in 4F.
  • 4D: invoices issued under rule 54(1A) by a registered person with the same PAN and state code as the ISD.
  • 4E (new): supplies through ECOs attracting TCS under section 52, other than reverse charge, reported by the supplier. Includes such supplies to SEZ for non-authorised operations.
  • 4F: supplies to SEZ units or developers for non-authorised operations (other than reverse charge). These go here, not in 6B.
• Table 5 (B2C large inter-State supplies above ₹1 lakh):
  • 5A now covers only supplies other than those made through ECOs attracting TCS.
  • New 5C covers such supplies made through ECOs attracting TCS, rate-wise with place of supply.
• Table 6 (zero-rated supplies and deemed exports):
  • A new column 4A, “Type of supply (Goods/Services)”, is added as a drop-down for 6A (exports) and 6B (SEZ authorised operations).
  • 6B covers SEZ authorised supplies with or without IGST, whether made through an ECO or otherwise.
  • Shipping bill details for 6A can be supplied later through Table 9.
• Table 7 (B2C other supplies) is split by ECO involvement:
  • Intra-State: 7A1 (other than ECO-TCS supplies) and 7A2 (through ECO attracting TCS).
  • Inter-State up to ₹1 lakh: 7B1 and 7B2, with place of supply.
  • Values are net of debit and credit notes, reported rate-wise.
• Table 8 (nil-rated, exempt and non-GST supplies):
  • Section 9(5) ECO supplies must not be shown as the supplier’s exempted supplies.
  • New Table 8AA allows amendment of nil-rated, exempt and non-GST supplies of earlier tax periods (rows 8A1–8D1), with a field for the tax period being revised.
• Table 9 (amendments, credit and debit notes):
  • Scope now includes Table 15 supplies.
  • A new column 3A, “Amendment relating to information furnished in table No. (Select)”, is a drop-down that identifies the underlying supply type for credit and debit notes. This lets GSTR-3B auto-populate them in the correct table.
  • 9A covers amendments of 4A, 4B, 4D, 4E, 4F, 5A, 5C, 6A, 6B and 6C.
  • 9B covers credit and debit notes on those tables and on Table 15.
  • 9C covers amendments of 9B.
• Table 10 (amendments to B2C supplies) is split into 10A1, 10A2, 10B1 and 10B2, separating ECO-TCS supplies from others, with the tax period being revised.
• Table 11 (advances):
  • New columns 2A (drop-down for the table the advance relates to) and 2B (GSTIN).
  • Advances can now be tagged to tables 4A, 4B, 4E, 4F, 5A, 5C, 6A, 6B, 6C, 7A1, 7A2, 7B1, 7B2 and 15.
  • 11B (adjustments) covers supplies in Tables 4, 5, 6, 7 and 15.
  • Part II amendments also carry the drop-down.
• Table 12 (HSN summary):
  • Separate sections for registered (12.1) and unregistered (12.2) recipients.
  • New Table 12A allows amendment of HSN summaries declared in earlier periods.
• Table 13 (documents issued): no change to the list of document types.
• Table 14 (supplies through ECOs, reported by supplier):
  • New columns 1A (type of recipient: registered or unregistered) and 1B (tax period to which the supply pertains).
  • 14(a) is a consolidated, ECO-wise, month-wise and recipient-category-wise summary of ECO-TCS supplies reported in Tables 4 to 10. This enables reconciliation with the ECO’s GSTR-8.
  • 14(b) covers section 9(5) supplies, where the ECO pays the tax.
  • Table 14A amendments carry the same new fields.
• Table 15 (section 9(5) supplies, reported by the ECO):
  • Recipient categories now include SEZ for authorised and non-authorised operations.
  • SEZ authorised supplies are zero-rated, so they can be made with IGST or under LUT.
  • Unregistered supplies are reported net of debit and credit notes.
  • Amendments are made in 15A(I) for registered recipients and 15A(II) for unregistered recipients.
• Other recommendations from the note:
  • Suppliers may, on a purely voluntary basis, link credit and debit notes to the underlying invoices. This helps recipients decide what to do on IMS.
  • Portal improvements such as tooltips and guided navigation are suggested.

3. FORM GSTR-1A (Amendment of Outward Supplies) – Proviso to Rule 59(1)

Previous difficulties

• GSTR-1A could only be used for the current tax period. It could not add or amend details of earlier tax periods.
• It could not be used to change the recipient’s GSTIN.
• Errors therefore could not be corrected before filing GSTR-3B. This pushed taxpayers to edit GSTR-3B directly.

Proposed changes and simplifications

• Scope of amendment widened:
  • The amended rule 59(1) proviso allows amending or adding details “for the said tax period or for an earlier tax period”, subject to the section 37(3) time limit.
  • Instruction 1 now covers particulars missed or misreported in GSTR-1 of the current or earlier tax period, including IFF details for quarterly filers.
• GSTIN correction allowed: the note recommends removing the restriction on amending the recipient’s GSTIN through GSTR-1A.
• Same structure as the new GSTR-1. Because GSTR-1A mirrors GSTR-1, ECO, SEZ and RCM supplies are classified the same way in both. The tables are:
  • 4A–4E: in GSTR-1A, 4C is the ISD-related table, 4D is ECO-TCS and 4E is SEZ non-authorised
  • 5A/5B
  • 6, with the type-of-supply column
  • 7A1/7A2/7B1/7B2
  • 8 and 8AA
  • 9, with the “relating to table” drop-down
  • 10A1–10B2
  • 11, with the drop-downs
  • 12 and 12A
  • 13, 14 and 14A, 15, 15A(I) and 15A(II)
• Availability and effect:
  • GSTR-1A opens after the GSTR-1 due date or actual filing date, whichever is later, and stays open until GSTR-3B is filed. For quarterly filers it opens quarterly.
  • It remains optional and attracts no late fee.
  • Its details flow into GSTR-3B together with GSTR-1. For quarterly filers, they also flow with IFF details of months M1 and M2.
• Flow to the recipient:
  • Supplies declared or amended in GSTR-1A flow to the recipient’s next open GSTR-2B.
  • Example (i): INV1 is filed in GSTR-1 on 8 February and INV2 in GSTR-1A on 15 February. INV1 goes to January’s GSTR-2B and INV2 to February’s.
  • Example (ii): if both are filed after the cut-off, both go to February’s GSTR-2B.
• Table-specific instructions:
  • Additional invoices can be added in Tables 4A, 4B, 5, 6 and 9B.
  • In Tables 7 and 11, a new rate cannot be added for a place-of-supply and rate combination already declared. Tables 10 or 11(II) must be used instead.
  • In Table 12, downward HSN amendments are entered with a minus sign for the difference.
  • Tables 10, 11(II), 14A, 15A(I) and 15A(II) amend details already declared.

4. FORM GSTR-2B (Auto-drafted ITC Statement) and Invoice Management System – Rule 60

Previous difficulties

• IMS was available on the portal from October 2024, but it was not notified in the rules.
• Taxpayers could bypass IMS and edit ITC in GSTR-3B directly.
• Credit notes were sometimes rejected or accepted prematurely.
• ITC distributed by an ISD as ineligible did not flow into GSTR-2B, so recipients had to reverse it again manually in GSTR-3B Table 4(B)(1).
• Ineligible ISD credit notes were wrongly reduced from eligible ITC.

Proposed changes and simplifications

• IMS notified by law (new rule 60(6A)):
  • Supplier documents from GSTR-1, 1A, IFF and 5, and import bills of entry (other than reverse charge supplies), are shown on IMS.
  • The recipient can accept, reject or keep each document pending.
  • Bills of entry can only be accepted or kept pending, not rejected.
  • Documents with no action by the time GSTR-3B is filed are deemed accepted.
• Pending periods:
  • Invoices and debit notes can be kept pending until the section 16(4) or 16(6) time limit expires. After that they drop off IMS.
  • Credit notes get a longer pending period:
    • Monthly filers: until the GSTR-3B of the second succeeding month is filed.
    • Quarterly filers: until the GSTR-3B of the next quarter is filed.
    • In both cases, the outer limit is the end of the month in which that return is due. The credit note is then deemed accepted.
    • Example from the note (monthly filer): a credit note reported by the supplier in the GSTR-1 for April 2026 (filed on 11 May 2026) can be kept pending until the June 2026 GSTR-3B is filed, or 31 July 2026 at the latest. After that it is deemed accepted.
    • Example from the note (quarterly filer): the same credit note appears in the IMS for the April–June 2026 quarter and can be kept pending until the GSTR-3B for July–September 2026 is filed, or 31 October 2026 at the latest.
    • Actions on IMS can be revised any number of times until the recipient files the GSTR-3B for the period for which GSTR-2B is being generated. If an action is taken after the 14th, GSTR-2B must be regenerated to reflect it.
    • An offline tool is available on the portal so that action can be taken on individual as well as bulk invoices.
  • If the recipient had already used ITC on the original invoice, interest under section 50(3) applies on the credit-note amount for the period it was kept pending (rule 60(6A)(v)).
• Structure of GSTR-2B:
  • The heading now names its sources: GSTR-1, IFF, 1A, GSTR-5, GSTR-6 and ICEGATE import data.
  • A “date of generation” field is added.
  • Table 3 – ITC Available.
    • Part A covers:
      • other B2B and ECO documents, mapped to 3B Table 4(A)(5)
      • ISD invoices, mapped to 4(A)(4)
      • reverse charge supplies, mapped to 3.1(d) and 4(A)(3)
      • imports, mapped to 4(A)(1), covering IMPG and IMPGSEZ, accepted or deemed accepted on IMS
    • Part B covers credit notes, which are netted off in the relevant tables. Reverse charge credit notes are netted off in 3.1(d).
  • Table 4 – ITC Not Available. All of this is to be reported as ineligible in 3B Table 4(D)(2). It now includes ISD invoices distributed as ineligible.
  • Table 4 Part B change: ISD credit notes relating to ineligible ITC are now mapped to Table 4(D)(2) instead of being reduced from eligible ITC in 4(A)(4).
  • Table 5 – ITC Reversal (Rule 37A):
    • Shows ITC to be reversed in 3B Table 4(B)(2), on or before 30 November following the financial year, where the supplier has not filed GSTR-3B.
    • It appears in the September GSTR-2B of the following year.
  • Table 6 – ITC Rejected (new):
    • Part A lists documents rejected on IMS.
    • Part B lists credit notes rejected on IMS.
    • Neither is to be availed or netted off in GSTR-3B.
• Generation and revision:
  • A draft GSTR-2B is generated on the 14th of the following month, or of the month after the quarter for quarterly filers. This happens only if the previous period’s GSTR-3B has been filed (new proviso to rule 60(8)).
  • If a taxpayer with no ITC to avail files GSTR-3B before the 14th, GSTR-2B for that period is not generated. Documents lying on IMS carry forward to the next period’s GSTR-2B.
  • The coverage windows in rule 60(7) are redrafted on a tax-period basis so they work for both monthly and quarterly recipients.
  • Rule 60(7)(iv) and (v) add pending items from earlier periods that are later accepted or rejected.
  • New rule 60(9): after any IMS action taken post-generation, a revised GSTR-2B can be generated on request before filing GSTR-3B.
• Supplier impact of rejections: the following, when rejected, are added back to the supplier’s liability in the next GSTR-3B or GSTR-5:
  • credit notes
  • upward amendments of credit notes
  • downward amendments of credit notes where the original was rejected
  • downward amendments of invoices or debit notes where the original was accepted
• Other advisory points:
  • ITC is shown as unavailable in three cases: the section 16(4) time limit has passed; the supplier and place of supply are in one State while the recipient is in another; or the ISD has distributed the credit as ineligible.
  • Reverse charge ITC on import of services is not part of GSTR-2B. It continues to be entered manually in Table 4(A)(2).

5. FORM GSTR-3B (Return) – Rule 61

Previous difficulties

• Auto-populated liability and ITC could be freely edited, which caused mismatches with GSTR-1 and GSTR-2B.
• Reclaimed ITC had to be shown in Table 4(A)(5) and also in Table 4(D)(1). This was confusing and error-prone.
• Liability of earlier periods was often corrected directly in GSTR-3B without correcting GSTR-1.

Proposed changes and simplifications

• Table 4 restructured:
  • New Table 4(AA): “ITC reclaimed which was reversed under Table 4(B)(2) in earlier tax period”. Reclaims no longer go through 4(A)(5) and 4(D)(1).
  • Table 4(C) is now calculated as (A) + (AA) – (B).
  • Table 4(D)(1), the reclaim memo entry, is moved to 4(AA).
  • Table 4(D)(2) is expanded to include ineligible ITC distributed by an ISD. This is auto-populated, so it does not need to be reversed again in 4(B)(1).
• New instructions:
  • Instruction 6: ITC in Tables 4(A)(2) and 4(A)(3) cannot exceed the reverse charge tax paid in Table 3.1(d) plus the balance in PMT-02B.
  • Instruction 7: the reclaim in Table 4(AA) cannot exceed the balance in PMT-02A.
• Filing condition (new proviso to rule 61(1)): where non-RCM ITC is to be claimed, GSTR-3B can be filed only after GSTR-2B for that period is available.
• Liability rules (new rule 61(1A)):
  • Outward supplies in GSTR-3B must not differ from GSTR-1 as amended by GSTR-1A or IFF.
  • Errors in earlier periods can be corrected only through the outward supply statement of the period in which they are noticed, subject to section 37(3).
  • Reverse charge liability can still be corrected by adjustment in a later GSTR-3B.
• ITC rules (new rule 61(1B)):
  • Non-RCM ITC must match GSTR-2B.
  • RCM ITC is subject to rule 86D(4).
  • Reclaims are subject to rule 86C(4).
  • An erroneous permanent reversal is corrected through PMT-10 and credited to the electronic credit ledger.
  • An erroneous reversal that should have been reclaimable is corrected through PMT-10 and credited to PMT-02A.
  • Both corrections are subject to the section 39(9) time limit.
• Result: GSTR-3B is meant to work as a reconciled return. Corrections happen at the source (GSTR-1, 1A, IFF, IMS and the statements), not by editing GSTR-3B.

6. FORM GST PMT-02A, PMT-02B, PMT-04 and PMT-10

FORM GST PMT-02A – Electronic Credit Reversal and Reclaim Statement (new, Rule 86C)

• Earlier: this has been a portal facility since August 2023, with an option to declare the opening balance of reversed but unclaimed ITC. It was not notified in the rules.
• Now: it becomes a statutory statement for every person eligible to reclaim ITC reversed earlier.
• Columns:
  • serial number, date, reference number, return period and description
  • ITC reversed in Table 4(B)(2) that is eligible to be reclaimed (IGST, CGST, SGST/UTGST and cess)
  • ITC reclaimed in Table 4(AA)
  • balance available, calculated as opening balance + reversals – reclaims
• Credits: reversals in Table 4(B)(2), plus PMT-10 rectifications under rule 61(1B)(v).
• Debits: reclaims made in GSTR-3B.
• Limit: a reclaim cannot exceed the available balance.
• Discrepancies: reported through PMT-04.

FORM GST PMT-02B – Electronic Statement of Tax Paid on Reverse Charge Basis and ITC Claimed (new, Rule 86D)

• Earlier: introduced on the portal from August 2024 for monthly filers and July–September 2024 for quarterly filers, with an option to declare an opening balance. It was not notified in the rules.
• Now: it is maintained for every person liable to pay tax under reverse charge.
• Columns:
  • reverse charge liability in Table 3.1(d) (IGST, CGST, SGST/UTGST, cess and total)
  • ITC on import of services in Table 4A(2) (IGST, cess and total)
  • ITC on other reverse charge supplies in Table 4A(3) (all heads and total)
  • balance available, calculated as opening balance + 3.1(d) liability – 4A(2) ITC – 4A(3) ITC
• Credits: reverse charge tax declared and paid.
• Debits: reverse charge ITC claimed.
• Limit: reverse charge ITC in a return cannot exceed that return’s reverse charge liability plus the balance. This prevents ITC being claimed without paying the tax.
• Discrepancies: reported through PMT-04.

FORM GST PMT-04 – Intimation of Discrepancy (amended)

• Earlier: covered only the Electronic Credit Ledger, Cash Ledger and Liability Register.
• Now:
  • Two new checkbox options are added: “Credit reversal and reclaim statement” and “Statement of tax paid on Reverse charge basis and input tax credit claimed”.
  • The form now refers to rules 86C and 86D alongside rules 85(7), 86(6) and 87(12).
  • Rules 85(7), 86(6) and 87(12) are restated to route discrepancy intimations to the jurisdictional proper officer through PMT-04.
• Contents: details of each discrepancy (date, type of tax, type of discrepancy and amount), reasons, and verification.

FORM GST PMT-10 – Rectification of Excess ITC Reversal in Table 4(B)(1) (new, Rule 61(1B))

• Earlier: an excess temporary reversal in 4(B)(2) could be reclaimed. There was no systematic way to correct an excess permanent reversal in 4(B)(1).
• Now: a self-assessment application to correct excess reversals in Table 4(B)(1) of an earlier GSTR-3B, subject to the section 39(9) time limit.
• Fields:
  • GSTIN, legal name and trade name
  • reason (drop-down)
  • tax period (month, quarter or financial year)
  • type of tax
  • total ITC reversed in 4(B)(1)
  • correct amount that should have been reversed
  • documents attached
  • verification
• Reasons in the drop-down:
  • excess reversal under section 17(5)
  • excess reversal under rule 38
  • excess reversal under rule 42
  • excess reversal under rule 43
  • reversal required to be reclaimed under rules 42(2), 42(3), 42(4) or 43(2). For this reason, the financial year is mandatory.
  • amounts that should have been reported in 4(B)(2) but were reported in 4(B)(1)
  • available ITC reduced by a credit note where ITC on the underlying invoice had already been fully or partly reversed in 4(B)(1)
• Effect: a correctly eligible amount goes to the electronic credit ledger. An amount that is reclaimable later goes to PMT-02A.

7. FORM GST DRC-03 – Intimation of Voluntary Payment (Rule 142(2) and (3))

Previous difficulty

• Tax is sometimes paid through DRC-03 after an audit, inspection, scrutiny or enforcement action. If the taxpayer then reported the invoice in GSTR-1 so the buyer could claim ITC, the liability auto-populated again in GSTR-3B.
• To avoid paying twice, taxpayers edited GSTR-3B, which created a new mismatch.

Proposed changes and simplifications

• The form is split into Part A, the existing payment intimation, and Part B (new).
• Part B has two tables:
  • Table 7A: details of outward supplies to registered persons on which tax was paid in Table 7. Fields:
    • GSTIN/UIN
    • invoice number, date and value
    • rate and taxable value
    • IGST, CGST, SGST/UTGST and cess
    • place of supply
    • type of supply, as a drop-down referencing the GSTR-1 tables
  • Table 7B: debit notes issued for such supplies, with the original invoice details and the revised document details.
• Rules:
  • Part B must be filed within 7 days of the Part A payment.
  • It is available for payments arising from audit, inspection, scrutiny or enforcement under rule 142(2), and for payments made against a show cause notice under rule 142(3).
  • It is used only for supplies to registered persons where the taxpayer intends to issue an invoice or debit note.
• Effect:
  • Part B details are populated into GSTR-1 and cannot be edited there, so they should be entered carefully.
  • The tax is not added again to the GSTR-3B liability, although interest may still be payable.
  • The recipient gets the ITC through GSTR-2B.

8. Related CGST Rule Changes and Draft Circular (Annexure C)

Other rule changes

• New rule 67B: if a recipient rejects a credit note on IMS, the related tax becomes payable by the supplier with interest in the next return. Interest runs from the due date of the period in which the credit note was originally declared.
• Rules 88C and 88D omitted from a prospective date. These are the existing intimation mechanisms for liability and ITC mismatches. They become unnecessary because mismatches are prevented at the source.
• Effective date: the mechanism is proposed to apply from the April 2027 return period.

Draft circular (in continuation of Circular No. 170/02/2022-GST)

IMS actions

• Keep a document pending, rather than accepting it and then reversing it in 4(B)(2), where the section 16(2) conditions (possession of the document, receipt of supply) are not yet met.
• Reject documents that do not belong to you or contain discrepancies. Rejection should be done carefully because a rejected credit note increases the supplier’s liability.
• Where a discrepancy is noticed, the recipient may instead keep the document pending and inform the supplier, who can correct it before filing GSTR-1 or amend it in GSTR-1A or a later GSTR-1.
• If the supplier deletes or updates a saved document before filing GSTR-1/1A/IFF/5, the IMS of the recipient is updated accordingly.
• Documents not available for ITC are not shown on IMS. These are documents time-barred under section 16(4), documents where the place of supply is in a different State, and ineligible ISD credit.
• If a bill of entry’s GSTIN is changed, the original importer sees a reversal entry on IMS that can only be accepted.

Amended documents

• If the original and the amended document fall in different GSTR-2B periods, act on the original and file GSTR-3B first, then act on the amendment.
• If both fall in the same period, the action on the amended document prevails.

Reporting in GSTR-3B

• Tables 4(A)(1), (4) and (5) auto-populate from accepted and deemed-accepted documents.
• Tables 4(A)(2) and (3) are self-assessed, within the PMT-02B limit.
• Permanent reversals (rules 38, 42, 43 and section 17(5)) go in 4(B)(1).
• Temporary reversals (rules 37 and 37A) go in 4(B)(2).
• Reclaims go in 4(AA). Until 4(AA) is live, taxpayers continue to use 4(A)(5) plus 4(D)(1).

Correction scenarios

• Credit note on an invoice that was rejected or on which no ITC was taken: use the IMS facility to accept the credit note and declare the actual ITC reduction, instead of rejecting it.
• Inadvertent rejection: ask the supplier to report the document again in the GSTR-1 amendment table, then accept it. This creates no extra liability for the supplier.
• Inadvertent acceptance: ask the supplier to amend the document in GSTR-1A or a later GSTR-1, then accept the amendment.
• Short reversal: reverse the shortfall in a later return, with interest.
• Amount wrongly put in 4(B)(2) instead of 4(B)(1): reverse it in 4(B)(1) and reclaim it in 4(AA) in a later return.
• Excess reversal in 4(B)(2): reclaim the excess in 4(AA).
• Excess reversal in 4(B)(1), wrong use of 4(B)(1) instead of 4(B)(2), or a credit note on an invoice already reversed in 4(B)(1): correct through PMT-10. Until PMT-10 is live, reduce the following period’s 4(B)(1) reversal by the excess. Where applicable, also report the amount in 4(B)(2).

Link to consultation note: Note on the proposed Alternate mechanism for making amendment of liabilities and input tax credit in GST returns

The Press Note can be accessed at: https://innovateindia.mygov.in/inviting-suggestions-for-the-proposed-alternate-mechanism-for-making-amendment-in-liability-and-itc-in-gst/