In the Crew 2 they give us an outfit, a leather jacket to be more accurate. So do not expect much.
For my experience in alphas and betas with ubisoft, they will make two alphas, 5-6 months before the release the first, 3-4 months the second, very few people have knowledge of them and they can't say anything at all, not even that they played. And Betas if they make one only, 1-2 months before the release. If they make two betas, closed and open, will be 2 and 1 month before the release respectively. There will also be a beta for magazines, youtubers, community managers .... within NDA for them.