Thanks again for advice/links.
Update: Am applying for Deputyship via a solicitor who is, I hope, prepared to waive her own fees for now. The court fees I've no choice but to come up with so an overdraft beckons. Social Services have decided to play total silly ******s over everything and seem determined to make my life as difficult as possible - hence the necessity to involve a solicitor to ensure all i's dotted and t's crossed.
I contacted Age UK and they are going to deal with the AA claim - they're happy to send a volunteer to the CH and complete the form with the help of Mum's advocate. At first they weren't sure that they could visit CHs (as opposed to a person's own home) to do this but got back to me that they could.
British Telecom are threatening to pass on MY details to a debt collection agency over Mum's unpaid phone bill...with which, good luck to them...
I eventually found a contact in the first hospital that Mum was admitted to and asked them specifically if they had an inventory of Mum's possessions on admission (thanks to Selinacroft for advising on this) and, lo and behold, they miraculously "located" them! Only taken three months...
Oh and another positive is that there are airlines that accept out of date passports as valid photo ID. Who knew?!