The primary difference between GSTR 2A and GSTR 2B lies in the cut-off date for filing GST returns. GSTR 2B reflects credits from returns filed up to the 11th of the month, while GSTR 2A includes those filed after. If your ITC is available in GSTR 2A after the 11th, you can claim it in the following month's return.
06 January 2022
2B credits related to GST return filed upto 11th of the month. 2A credits include GST return filed after 11th of the month. This is the reason for the difference. ITC in case of credits available in 2A after 11th can be taken in next month return.