SPR 10097712 has destroyed another drawing. Sometimes when you redesign a part you lose the drawing mode Datum A feature. If you delete the entity that the GTOL was placed upon (surface),and the Drawing mode Datum A was placed upon this GTOL, then you have permanently (no fix) screwed your drawing per no Drawing mode Datum A allowed -- ever. Skips to Datum B 100% of the time... The Datum A is no where to be found using any utility. And of course is not on Drawing Mode Annotation Tree. I can create this bug 100% of the time. The problem is avoiding it. You are just working on the part -- drawing not even up in memory, and you can permanently destroyed the drawing if later the no broken GDTOL with the datum is deleted. I have 5 sheet E size drawings that have taken days to recreate. And we are ITAR, can never send PTC the files to be fix -- per PTC's request. Anybody see this? Anybody fix this?