Input tax credit availability tied to GSTR-2B for refund claims, impacting refund admissibility and procedures. Refund of accumulated ITC under Section 54(3) is restricted to ITC reflected in FORM GSTR-2B for the relevant tax period or any prior tax period where the credit is available, applicable to refund claims from January 2022 onward. FORM RFD-01 undertaking is amended to remove references to the omitted Section 42 and deleted GSTR-2/GSTR-3, while applicants must still undertake repayment with interest if clause (c) of sub-section (2) of section 16 is not complied with. Refunds of integrated tax paid under Rule 96A are admissible upon subsequent export or receipt, but interest paid is not refundable.