Hi Tom
Welcome to the forum...thats a great story!...I wish you all the best with Greenbean.Its a tricky one,I think you have been given expert advice there.
It could be a shedding about to happen or it could be the onset of winter behaviour..it may even be that he is still well nourished from the large mouse,(maybe a much larger food item than he normally catches).Hopefully the next week or so will give you an answer...keep us informed how you get on .

Good Luck Paul (in the U.K.)