2 years they had in theory but the question is how much effort they put into it early on since they could not completely neglect D1 so if they split the team 50/50 that means they had 1 year if they split it 10/80 early on and from alpha made it 60/40 followed by 100/0 from beta onwards then it would give them far far less time... well i can explain to you but since you are still in school i doubt you understand how a company works...