I would guess that the game will enter the beta stage when career mode is released, and will eventually be fully released.
Because beta generally means that the game or software is "feature complete" and it is just out for final bug testing and fixing. Beamng is still very much an alpha game. The physics may be very well out of that stage but the game Beamng is still very much lacking in game features.
It's a big project by an indie dev team, these things take time. It's not like it's the only game in the world to be in early access for a long time.
Personally, I don't see a point in Beam moving from Alpha. at least not right now. Consider if, 3 years ago, they had moved to Beta. Thi implies that the core of the game is done, so development has moved away from the core to the secondary and tertiary loops. Beam has no real set seconday loop unless you are playing a scenario. Quick explanation, a Primary loop or 'core gameplay' is what the player does from second to second, which is drive in this case. the Secondary loop is what the player is doing from minute to minute, or what the point of the primary loop is trying to serve. In Beam's case, you could be driving to get the fastest time on a track, or evading arrest, or drifting, but note that atm, there is no set secondary loop. The game doesn't tell you to start drifting, racing or evading, unless you start a scenario. you sorta just decide to atm. Tertiary loop refers to the overarching goal. the answer to what we are here to do. what connects all these pieces to make a story. In most racing games, the primary loop is driving about, the secondary loop is racing/ evading police, and the tertiary loop is to become the best racer. Basically, Beam has no tertiary loop. Obviously, Beam is still working on the primary loop, which is a good thing. Super Mario 64 wouldn't have been half the classic it is today if the devs hadn't kept Mario in a basic room for a year and made controlling him fun. A lot of SM64 contemporaries had the primary loop be 'idk just walk around and sometimes hit a button to jump or something'. The Primary loop is where the game is. if you have a primary loop that isn't fun, like if the combat in an RPG is a chore, then it takes away from the game. TLDR: I'm glad Beam has taken 6+ years to nail what really matters, the driving and physics. This is a good thing.
Tell me, has BeamNG Gmbh announced that they're stopping updates? No, they haven't. So it'll stay in alpha, i'll see myself out.
I'll just throw in my two cents here. A rushed game is usually terrible. That point really can't be disputed. However, keeping your game in development for an extremely long time isn't exactly the best idea. Ideally, a development team should find a balance in between the two, working at a decent pace without rushing, but not taking forever. It has been well over three years since the "Something is still on the horizon" blog post, and a lot has changed in that time, and I would assume that much more has changed behind the scenes. At this point, we need a second major blog post. Be it @tdev , @MrGantt , or whoever would be responsible for producing such a blogpost, I strongly believe that someone in the proper position for writing said blogpost should sit down and produce another blog post of this type. I remember how long it took to write the previous one, and I know that it is a ton of work, however, for the most part the community is completely in the dark as to what the overall goals and desires of BeamNG are regarding the game itself, and the main source of information we have to go off of (the older blog post), is over three years old, thus likely very outdated. Hopefully a new, updated blog post would allow there to be a shared understanding of what BeamNG intends to do with the game, clear up many misconceptions, and allow for productive dialogue between the community and the developers.