When I use a drop rind I
When I use a drop rind I base my heat up schedule on the initial thickness of the glass and slow it as it reaches the temp in which it starts to move. I am usually very conservative at the top when reaching the temp that the glass begins to drop, using a lower temp and longer hold. Too hot, too fast and your drop may end up on the kiln shelf. Once the drop reaches the shelf and has the base that I want, I flash cool to 1100F, then anneal, again basing my anneal on the original thickness of the glass.