Do we have to leave our Zcash under a shielded or transparent address? Or would it not matter? Sorry I know its early just trying to get a head start on all of this.
Sapling shielded addresses and transparent addresses are fine. Sprout shielded addresses will likely be supported too, but a final decision has not been made on that yet.
I repeat: There is no need to move your ZEC out of Zcash Sapling shielded addresses. If you have your ZEC stored in the Sapling shielded pool, you'll have the equivalent amount of YEC in the Ycash Sapling shielded pool.