I've worked for two different banks. One thing I know, is that anything that is IT/systems/network related takes FOREVER to change. They have so many layers of people, auditors, committees, boards, etc that have to all approve anything like this. Probably have to re-write some parts of the bank IT policy someplace as well.
I think the app guy could make this change in a few hours, but banks are just so highly regulated and monitored on the IT side, they can't just push out an update before it goes through all those layers of checkpoints.