Initial details regarding Valve’s plans for roster changes after The International have apparently been leaked to GosuGamers (and there was a whole Reddit thread about it.)
According to the leak teams must have a stable roster, with up to two standins, ready to go by September 1 this year if they wish to be invited to the first Dota 2 major that is set to take place in the Autumn. That is just three weeks after The International 5 concludes, meaning the traditional months long roster changes will hopefully be a thing of the past.
The rumour also suggests that Valve will be taking an active role in managing player transfers and December 4 was also mentioned as an important date, whether this will be the cut off point for the second major or related to a transfer window remains to be seen.