As I've said before, there is a push from imagineering to get Tiana finished and open much sooner than the announced date. The most aggressive people want it done before the end of summer next year. The "late 2024" deadline is apparently being imposed on them artificially by the executives. They want to stretch out the development costs across a longer period of time in order to make the books look better.
So all that said, I have no doubt they should be able to make the current deadline fairly easily. They appear to be moving at a brisk pace on the exterior and i'm sure substantial infrastructure work is being done on the inside as well (perhaps even more quickly than the exterior). They've already got a lot of the interior props and characters built and ready to install as well. More than you would think they have given the piddling amount they've shown so far (that naked Louis endoskeleton from D23 is far from all they have).
That said, I don't know if the imagineers will get their wish to open it sooner anymore. A lot of this push was from several months back and was contingent on being able to get other projects across property greenlit. Like the AK and Beyond Big Thunder stuff. D23's revelations of empty non-committal blue sky stuff have made it fairly clear that they failed in their efforts to get a greenlight for anything in those areas. So I wouldn't be surprised if the executives also put an end to hopes of getting this done earlier as well.
For the record, despite what Splash Archive claimed, I still don't fully buy that his renders showcase the full AA roster in that finale scene. They're clearly in a non-finalized state. Two of them are testing out incomplete figure arrangements within the same scene (the characters in one of them are even still in the t-pose stance), one of the renders doesn't even have any figures at all. There's at least three more characters who will be present that aren't accounted for (Big Daddy and the King and Queen).
There are a ton of empty spaces surrounding this platform, landings and balconies that look tailor-made to hold extra AA's. I don't really understand why they would construct these platforms and not put any characters on them. The Tiana's Palace facade from the film doesn't even have most of these spaces. It would be a lot of empty wasted space on a large structure in a massive sized room. It would be even more strange if the huge celebratory finale had fewer figures than several of the prior scenes throughout the ride.
So until I see substantially more evidence that there won't be more figures in this scene, i'm remaining skeptical. I think Archive's renders ARE real, but I have my doubts that they're as final as he claims and are accurate to the full character roster. We'll see though.