You can still Efile,.. Schedule B will be available on 3/31/22. Print that schedule out and add it as an attachment showing the correct carryovers reconciliation. 
Override the carryover to 2021 and 2022 lines on foreign tax credit computation worksheet, Leave them blank.
You will need to manually add amount to part III line 10…my two errors disappeared. I think this should work but won’t really know until I see Schedule B…