I think you can go when everyone ready. Four leagues have already drafted. But all leagues start Jan 24, so either wait before or after draft. Prob better to have longer to tinker (or maybe not?)
Draft ANYTIME - as soon as your 12 are in everyone can set as ready and draft! Opening day is Jan 24th for everyone, so drafting early just means a longer pre-season between waivers and opening day. Five of the 14 leagues have already drafted.