But... there is no Battlefront III. It was cancelled.
Well, sort of. It was reworked into Battlefront: Elite Squadron for the PSP. Could BF3 Classic be related?
edit: I should perhaps add that I don't think any official sources have ever claimed BF3 was turned into Elite Squadron. I don't think I've ever heard anyone say it. But the game has the same lead characters present in old BF3 footage, even some of the exact same cutscenes, as well as the same new mechanics. So like, it's Battlefront III, but it was on the PSP, so nobody realized.