Running new GL and traditional GL at the same time

Refer to the following OSS Note for all migration queries

1070629 - FAQs: New General Ledger Migration

Read question 23 for  "Running new GL and traditional GL at the same time"

23. You want to configure a new company code with the new general ledger. The existing company codes use the classic general ledger. Can company codes use different general ledgers (classic and new) in the same client?

The implementation of a new company code and the transition from the classic general ledger to the new general ledger are two different projects which you must schedule at different times.
You perform the migration from the classic general ledger to the new general ledger at client level and it affects all company codes in this client.

Because the new general ledger is activated at client level, the new general ledger would be active for all company codes, not only for the new company code. This would mean that the new general ledger is active in the old company codes, but there was no migration from the classic general ledger to the new general ledger. This is not possible.

Therefore, it is not possible to start with a new company code in the new general ledger while the classic general ledger is still active in other company codes in the same client.

First implement the new company code. Then set up the project for the transition from the classic general ledger to the new general ledger.

Alternatively: First set up the project for the transition from the classic general ledger to the new general ledger and migrate the data to the new general ledger, then implement the new company code.