At this point, you might as well not bother starting Baldur's Gate 3 in early access, and that's according to its own developer. Progress in the early access version of the lengthy RPG will not carry over to launch on August 3, so at this point "a purchase of early access is essentially a pre-order," Larian Studios says. Players have been tackling Act 1 since its early access launch in 2020, but if you go make your dream character and start the story right now you'll be stuck redoing it all very soon.
"We’re recommending that players don’t buy the early access version of Baldur's Gate 3 with a view to play through that content, partly because it’s out of date but mostly because we’re so close to launch," Larian says in its latest community update. "Essentially, the game is so vastly different that it’s not possible to make those save files compatible."
Again, the early access version of the game is still playable. Larian just recommends you don't. Unless you've got a particular desire to experience and catalogue the early access state of the game for posterity's sake.
If you do buy the early access version between now and launch, you will still get all the digital goodies that come with the Digital Deluxe version of the game (dice skin, song pack, digital OST, art book and so on) except not the 72-hour head-start that was originally advertised—another bit of launch info that was clarified in the community update—because with the launch getting moved forward PC players are already getting a month head start, aren't we?
I'm certainly not disappointed that Baldur's Gate 3 is arriving ahead of schedule since I'll have more time to spend in the Forgotten Realms before Starfield launches, but it sure has resulted in a lot of scheduling clarifications.
Just to make absolutely sure everyone's on the same page, one more time:
Do Baldur's Gate 3 early access saves carry over to the full game?
No. Baldur's Gate 3 early access saves will not transfer to the full game.
If you've already played in early access, say goodbye to your character. Time to start fresh with the full release, because "the game is so vastly different that it’s not possible to make those save files compatible."