Transferring in Foriegn Currency into relevant currency account

Just to check… I have a Dirham sub account with you, i have Dirham’s held in another UK based FX dealer account, i can transfer those Dirham’s into the Dirham account with no issues or charges so long as i put in the correct reference number. Also when i am in UAE spending those Dirhams it takes the money in Dirhams from my Dirham account (so long as the transaction is processed as a Dirham payment)? This is the way it works right?