For each trust account in TAS, you must enter a transaction to remove funds from the old bank, and then enter a transaction to add funds to the new bank.
If you will be writing a check from the old bank to the new bank, you can write a single manual check that encompasses all trust accounts, and then enter the check information into TAS for each trust account showing that the funds were removed from the old bank account. Once this has been completed, you can then enter a deposit for each trust account using the new bank account.
Alternatively, if you are not writing a check from one bank to the other, you can enter EFTs instead. When entering EFTs to remove funds from the old bank, enter a positive EFT amount. When entering EFTs to add funds into the new bank account, enter a deposit.