Whether ITC in Dec 2021 GSTR 3B is mandatorily required as per GSTR 2B?

When the transactions were done on December 21 then at that point of time old rule 36(4) was in force. Therefore, in our view,  it would be in order if the ITC of December is availed by referring to GSTR 2A.

source https://www.caclubindia.com/articles/whether-itc-in-dec-2021-gstr-3b-is-mandatorily-required-as-per-gstr-2b-46632.asp