Maybe gone on holiday, maybe retired.
Last time I saw her which was about 6 weeks ago she was talking about moving to another flat so maybe she's doing that. A recent review on here said she was retiring though (and she had mentioned to me in a previous punt that she was thinking of it too).
Personally, I hope she comes back as she's excellent. I've seen her many times and would like to continue to do so but if she doesn't return I guess all I can do is wish her well.