auto-saving data in joined linked SQL tables

I have a query behind a form that joins two tables with a 0-1
relationship. The backend DB is SQLServer. There's an Identity column
in Table A that is used to join with Table B. The joined column in
Table B serves as the tables PK. Attempting to save the data on the
form fails, because PK for Table B isn't populated because, it seems, in
Access, Identity columns for my SQL tables aren't populated until after
the record is saved (Access tables generate AutoNumber column values as
soon as data is entered into a new row).

A work-around would be to write code to save the data to the two tables,
but there are oodles of fields, so this would be cumbersome. Do I have
a simpler option?

Thanks in advance.