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He has been there roughly a year. I am sure he would be happy to say he has been there just over a year.
The property is a three-bedroom house, and that is in part why I think the council will take it back. Given the lack of available housing stock, etc.
I have just spoke to Age UK on this, and they've advised me to write to the council concerning the succession, make his case as best we can, and then await a decision. She's implied, however, that they will most likely rehouse him, rather than let him stay there.
Thank you all for your suggestions!