Where can I find the mapping or configuration defined that ensures P&L accounts use AverageRate-FCCS

We would like to confirm the configuration or logic used in FCCS to apply average FX rates(FCCS_AverageRate) to P&L accounts during the currency translation.

Specifically, we want to know.

Where is the mapping or configuration defined that ensures P&L accounts use Average Rate.

Is this driven only by the Account Type (Revenue/Expense) in the Account dimension?

Is there any way to override this configure exceptions?

Please advise how this is controlled within standard FCCS setup and if any custom setup is supported