oh ok other seasons were not on devpost please I will look for them for you
Season 1 = Forum (I think)
Season 2 =devpost
Season 3 =Devpost
Season 4 =Dorahacks http://dorahacks.io/hackathon/hackatronS4
Season 5 =HackerEarth https://hackatrons5.hackerearth.com/
Season 6 =Devpost