Looks like the visit to the Avion by some urbexers was well-timed: over the Easter break my bother-in-law emailed me:

Just thought I’d let you know that they’re demolishing it ……we went to Morrisons today & the back half has already gone.

I’m pleased to say that it’s not actually being demolished, or at least not all of it: the planning documents (PDF, 80kB) on Walsall MBC’s site don’t go into detail (and I can’t find anything more detailed), but they do say:

Part demolition and alterations and change of use to Class A4 (drinking establishment) with external seating area, extension of adjacent car park, new boundary fences and pedestrian access.

which pretty much confirms the Wetherspoons story.

They’re not mucking about though: I called in at Morrisons on Monday, and you get a good view at what’s going on, and they’re demolishing a good part of the large auditorium behind. At least there’s nothing architecturely significant about it- pretty basic 1930s construction, brick, steel girders, and a sheet roof.

From the side, it’s clear how much has been demolished:

What I’m not sure about is how much is going to be demolished, or how much is original: it’s a big old shed of a building, so clearly they won’t need all of it. Can’t help but think that the top of the frontage, on the other side, would make a nice roof terrace…