It would be cool, but if you asked me, I'd do it gradually with each new update. Whenever a new update comes out, you could unlock only the Patreon scenes from 3 or 4 updates ago.
I've only been playing this game for a little while (and it's really good, by the way), but for example, if version 1.7 comes out, you could unlock the exclusive scenes from version 1.3 or 1.4. Then every new update would keep unlocking the older Patreon scenes.
That way, Patreon would still keep its exclusivity because supporters would get access several months before everyone else. I think that would be a pretty good balance.
This is just my opinion as a player. It might not fit with what you have planned for the game, but I still wanted to share it in case you find it interesting.
Anyway, that's all. Sorry for the long message. I'm really enjoying the game, and I just wanted to share my humble opinion.