Would an invol schedule change (in advance, rather than day of travel) on an award ticket booked by another carrier (say BA or AS) be subject to AA's rebooking policy? Or, would it be kicked back to the ticketing carrier who would then have to find open award space again?

I figure it's the latter, which would make booking with an AA partner a bit of a risk. I don't think those partners can force award space open, either, if there isn't any.