Given that they were the ones to make the mistake I'd say that the onus is on them to accept repayment at any rate that is convenient to your mother, even if that's £1 a week for the next 19 years, as occurs sometimes when people get a County Court Judgement against them to repay debts. However I know nothing about the workings of Councils, but MP's are usually quite good in this respect - use this online service to give them
full details and permission to enquire on your mothers behalf
WriteToThem.com, also contact the council housing officer as you mother may be evicted and require council housing. The Council
hate having to house people and given that they will often pay for legal representation to help prevent it if at all possible, I'm sure they will attempt to resolve the situation rather than have her made homeless by another arm of the Council. You could also involve the local newspaper. It's a matter of tactics when you do so as you could use it later on to escalate matters if you don't get the right response
There's another good forum here Usenet -
uk.gov.social-security for benefit queries - frequented by many serving and former council employees. They will be able give you detailed help. As spam harvesters harvest email addresses from Usenet, use a free throwaway address like
Sneakemail.
Hopefully you get the idea - attack them on as many fronts as possible. Good luck - let me know how it turns out

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