Not sure if I mentioned this before but ice packs are really useful for flipping slabs that aren’t stable. Put one under the oven tray and it’ll harden the slab enough to where you can edge it off the side of the tray so it loosens enough to where you can put it face down on a clean parchment that’s also on an oven tray that’s on an ice pack and gently peel off.
2 ice packs 2 trays 1 clean parchment.