I was in my local TTB bank, yesterday, getting the account verification letter for my extension application. I was told that the branch was to become one of the pilot scheme branches, whereby it will become 'paperless' and will no longer provide such a letter. The change in policy is imminent.

I foresee that this will cause problems if Immigration still insists on the letter being issued on the application date, after a transaction has been made.

It is likely that any account statement or letter will have to be obtained from a branch that has not gone 'paperless'. 12-month statements, for those of us using the monthly income method, have to come from Head Office anyway so might not be affected. Rather depends on exactly what 'paperless' actually means. If a branch no longer even has a printer and what comes from Head Office to the branch is a digital file then how is this going to work?

Maybe Immigration will modify their system - but don't hold your breath on that score!

I'd request a letter from the branch confirming that in future they are unable to offer the letter requested by Immigration, and present it to Immigration for their reaction.
I suspect they'll tell you to change banks.

Unless all banks decide to go paperless, then and only then would Immigration be forced to change the requirement.