Loyalty counts for zilch. I was (still am technically because I am still waiting for them to close the account) with the Halifax for twenty years. It wasn't always in credit, but always managed well, and I had an agreed overdraft.
Someone there decided I was no longer entitled to the overdraft (some rubbish about the account not being used enough to warrant one (it wasn't my main account)) and took it away without telling me. Actually they did tell me, but by an email at a time I had no computer, so I didn't know.
End result, they charged me for unauthorised overdraft, wouldn't accept they were in the wrong, leaving me no alternative to end the account. That was a year ago, and I am still awaiting the return of the fees and the closure of the account and the money in there. Letter after letter they have had too, and have thew cheek to say they can't refund money because of this OFT lark, despite me saying that doesn't apply here.