Multi-currency groups lose hours reconciling CTA plugs that nobody can explain. Agree the rate source and which rates apply to P&L versus closing balances, then stick to them across entities.
Intercompany balances denominated in different functional currencies create FX that should not simply vanish in elimination. Document how differences are treated and whether they land in CTA or profit.
A short rate file in the consolidation pack — period average, closing, and any special rates for significant transactions — prevents subsidiaries inventing their own conventions.
If CTA moves sharply without a matching net investment story, investigate before locking the group accounts.