The fact that you have to rely on all these bits of hearsay and empty assurances that they had a plan, doesn't help convince me they were actually going anywhere. Really only hammers home the point, and helps me understand why Square Enix felt they had no choice but to hand it to a different lead and team.
Its common knowledge that nomura versus teams were assigned by SE on main line XIII entries during PS3 era. As Versus 13 was not the mainline entry and was too dark and voilent to be a mainline entry hence he was asked to brighten up the game so it could get a wider release, hence it was during this time Nomura floated the idea of making XV a musical as the concept was heavily inspired by Shakespear Romeo and juliet, but the idea was quickly shot down by his team and SE, In process of making it less dark Nomura pitched various stage reboots which would have set them back even further, Hence SE made tabata the incharge.. the only thing Tabata did was cut down the story to make a shorter narrative for a single game, in process ruining the game.
So only if SE didn't force Versus on to main line entry we would have had nomura's game in the same year as tabata and preparing for the sequel.