Some warping/deformation due to the ramp down being overly rapid. I don’t particularly want to make the unflattened/unmounted option a regular thing. You’ll have to manually delete about 1mm of vitrified abrasive.
Probably have to wait a couple weeks. If you wanted one unshaped, unflattened, and without the glass base, that could be arranged sooner. the limiting factor is the time it takes to flatten them