The Patch Installation Notes of Sage X3 2024 R2 (12.0.36) contain the following details regarding this change:

Setup > General parameters > Parameter values (ADPVAL)

We provide the option to activate the stock valuation by period (PIT valuation) at folder, legislation or Site level for anglo-saxons stock accounting.

A new parameter STOVALPER has been added in STO chapter and ACC group:

If set to ‘No’, no additional records are created and processed for stock valuation by period process (PIT)
If set to ‘Yes’, stock valuation by period process (PIT) is activated. We can set it to 'Yes' for anglo-saxons stock accounting only (parameter ACCDETSTK set to 'Yes')

Note: in all cases the parameter STOVALPER is set to ‘No’

So for anglo-saxons customers which are using this PIT functionality today, they must set it to ‘Yes’ manually to be able to continue to use this PIT functionality after the update in 2024.R2