I don't think there's any reason to believe it wouldn't just be the four rounds they say it's going to be. The Seasonal Show CD is probably going to come out as an interim (but it's not clear if that's going to be a project that has drama tracks or not), or there may be something similar to Exhibition Show from the Stage Battle rounds, plus whatever after-battle dramas the winning teams from each round get. Overall, though, I'd assume it's just going to be the four rounds and then a finale (a'la LIVE and ANTHEM).

Remember that RtL was six rounds (FATE, RAGE, SHOWDOWN, WILL, TRUST, and REVOLUTION) that took place over two years, so four rounds in one year is pretty brisk.