Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - General Early Access Announcement Trailer

SniperHF;
If you have 2 copies of the game in the tier rewards, that will give you 2 keys for the beta. You'll be able to choose each available key separately, so can split them between GOG and Steam.


Alrond;
There was some discussion about allowing money to be added (via Paypal) for add-ons (excluding extra copies of the game). As long as no issues cropped up with that, there should be a Kickstarter update at some point with instructions and deadlines, etc.

EDIT: eventually it was decided not to do this. Either adding the functionality to the Vault or manual additions would divert resources from working on the game, and those who would need to do either are already quite busy.