GST 105% CALCULATION QUERY

if previous month invoice amended it is autopopulated in that month GSTR 2A, we need to consider this amendment in current month 105% itc calculation? if yes what amount of amendment value full value or differential value? ie,
1.if invoice value Rs.150000+18% GST in December 2020, after amendment Rs.180000+18% GST But this amendment made in january 2021 and after amendment it is autopopulated in GSTR2A of December 2020 then this is amended invoice is considered for 105% itc calculation in January 2021 what amount Rs.180000+18 GST or 30000+18% GST?
2.if invoice value Rs.180000+18% GST in December 2020, after amendment Rs.150000+18% GST But this amendment made in january 2021 and after amendment it is autopopulated in GSTR2A of December 2020 then this amended invoice is considered for 105% itc calculation in January 2021 what amount Rs.150000+18 GST or 30000+18% GST?
what to do in both situation?
Situation one we need to consider this as itc for 105% calculation in january 2021?
Situation two we need to reduce this itc from 105% calculation in january 2021?