@Tricky
So you are saying there is no way to wait until the blitter finishes?
Sure there is, but your proposals are not working.
I don't see why, as you have to be on the workbench screen anyway to run another program.
You say it is possible to write such "swap" program. I still think it's not very stable solution, various things can easily break it. Lets agree to disagree, shall we?
I will hold my POV until you provide a working chipmem extender program. :-)