well the idea of 3 platforms before 5th generation do not makes much sense either.,, i mean what are the supposed benefits that it will give us??? Specially considering the time line by which we can start getting J-31. Considering that, a fifth generation plane along with future JF-17 blks and a few F-16 are a much more better solution. Both in procurement and also keeping them operation. Inducting a third platform will just increase the operations costs. Upgrading and keeping the evolution of JF-17 MUST be the priority, for next step, we can go for fifth generation then.