Unfortunately, loosing venues and moving on is (as Tattie Bogle says) quite common.

Of the ones I've known go, some have been lost following the change of landlords. Others have become unworkable. Examples of the latter are a pub in Bangor which decided it wanted to catch customers on their way to a night club, one on Anglesey that started hosting reggae nights on the same night as the session and, closer to where I live now (I'm on the North Norfolk coast), one in Norwich and a clash with football on tv (couldn't hear one another over the cheers, etc.).

We rarely get out to sessions these days but as things stand, I think the Norwich ones have a good venue. The Gatehouse hosts 3: A very "serious" (the "core" players have the 1000+ tune repertoires) one on Wed, a more relaxed mostly Irish one on Sun and a sort of anything goes tunes and songs one on a Thu. I'm not sure if it's still going but it might also still host a monthly mostly English one on a Sunday afternoon.

I like the acoustics in the rooms (wed uses the main bar, the others use a sort of side bar) and the landlord seems to want the music. As an added bonus, he's probably the cheapest pub in the city for drinks.

Hope it keeps going but you never know... I just think the sessions have a good thing at the moment and hope that others wherever they are playing who have somewhere stable and nice to play in value what they have.