Guild Wars 2

Does it start right after the current one ends? If not, then will we not be able to progress through divisions while we wait for the season to start? How does the whole thing work?

Season ends, ranked becomes unavailable for a bit like it was first month of HoT, balance patch, then new season starts.

Expect 1 or 2 weeks, maybe longer.

balance patch (hopefully right after the season ends) and approx 2 weeks after balance patch is when the season will reset.

also likely everyones division will be reset between seasons

there will be no season 2 ,everyone will leave the game until then.