I would love to know if they plan on leaving it so you can change your prepared spells at any time (it could be a holdover from DOS), or if they plan on fixing that so it’s like D&D. It’s a bit hard to evaluate party balance during EA unless we know either way.
I found (probably linked somewhere on this forum) an old interview/stream/... in which they said something like we would only be able to prepare spells and level up at camp.
I think it was in the first interviews about the game. I hope they didn't change their mind.