Join Date: May 2011
Location: Edmonton, Alberta, Canada
Check your existing lease agreement. If the contract says you're entitled to certain amenities and you're no longer getting them, the barn owner has breached his part of the agreement and the contract is, for the most part, null. If s/he is not maintaining their part of the bargain, you are no longer required to do your part, which was providing notice upon relocating.
I board at a barn with a lot of great amenities and I keep my mare in the pasture. I get full access to all of the facilities, but the lesson program gets first dibs on the arena. If a boarder wants to ride during a lesson, they are asked to stay out of the way of the lesson kids, whether it's in another arena all together, the parcel of land across the road or in a corner of the in-use arena. If it's a jumping lesson, only the lesson students are allowed in the arena for safety's sake. All lessons are scheduled weeks in advance, on a public whiteboard, so it's easy for me to schedule my riding time around lessons. If I was in your situation though, I'd be very upset about the sudden lack of amenities I'm paying for.