Not having much success here I'm afraid...
There isn't actually a hotel in Keswick called the Skiddaw House Hotel - there's the Skiddaw Hotel (off the Market Place) and Skiddaw House itself, which is a Youth Hostel at the back of beyond (down a long track past Threlkeld).
I'll probably be there from Tuesday through to Fri/Sat, so a Sunday session's no use.
I seem to recall an earlier thread bemoaning a rather unwelcoming singers/musicians' night somewhere in Keswick, one to avoid during the summer - but this is february.. so any other ideas?