How to fight banks that keep your savings prisoner because you want to take ‘too...

Over what period do these internal limits apply?

I've not had the problem closing an account before, but unless the period was £10k in a week or something it strikes me it would be less hassle to just transfer £10k today, £10k tomorrow, etc and then close the empty account. Or £10k to one account, £10k to another, £10k to a third if that was permissable.

Either way comes to mind before ringing the bank as it would seem to take the same week (assuming the full £75k as was for FSCS cover) to get the money across, but without the hassle of explaining things to several people and being passed from pillar to post, having to chase calls or deal with them communicating with you at their choice of time.

I do see the principal in it with regards "easy access", but they're never going to drop the security limit even if it varies over time, and any process of not going into a branch (if you've signed up online there might not even be a branch within 100 miles) is going to take time to process paperwork due to the way the post works.

With the lost interest again I see it should be covered, but equally look at how much extra time you're spending going through the ringing up etc and see what it's worth as an hourly rate (it'll be a lot lower if you're transferring money during the process as well), and what you're not doing because you're spending time ringing the bank.

It seems like something that ought to have been in the t&cs. If a bank(?) is going to take deposits greater than its' withdrawal limit, then it should at least say how to withdraw them and how long it will take.

You did read the t&cs, didn't you Martin?