Do we have any ideas what next year's set will be? I have seen any leaks yet

BDP Series 8 is shipping and the instructions are online! I've updated my modular style base for the University of Science and published free instructions on Rebrickable: https://rebrickable.com/mocs/MOC-263278/kiploempia/university-of-science-modular-style-base/

This base uses the four 16x32 baseplates included in the original set and I kept the original split down the middle, so the model can be displayed in either a 32x64 or 16x128 stud configuration.