I waited a while and proceeded with removal which involves a vacuum cleaner and a lot of care. Ooops, there goes part of the model, hang on a minute..... It looks like the bottle of binder actually just contains water! I can see that the parts printed OK but they have zero structural integrity!!
Then I came to re-spread the powder and the old issue of intermittent spreading reared its head. Not sure what it causing this, it never happens during the build and it can happen even when the feed bin is lowered and no powder is being pushed. I have added grease to the linear bearings too. Hard to diagnose the issue and no useful error messages. Perhaps the roller mech is having problems and the gantry stops because of that or perhaps there is just too much friction in the gantry but that makes no sense as it always works fine when printing. Mysterious!
I really wish I had finished my homebrew Zcorp printer, it would probably be less hassle than this ;)