Ledger loaded into FCCS already has a translation reserve balance, what movement to net this off?

Summary:

Ledger loaded into FCCS already has a translation reserve (CTA), what movement do we assign to the migrated translation reserve account so it nets off with the calculated translation reserve account in the FCCS Cash Change hierarchy?

Content (required):

We are loading a ledger that has already been translated before being loaded into FCCS and therefore already has a balance on a translation reserve (CTA) account. This ledger is then translated in FCCS into its parent currency. We want to net off the pre-FCCS translation reserve with the FCCS calculated translation reserve in the seeded cash flow - Cash Change hierarchy.