TerraN_EmpirE
Tyrant King
Most air forces are. But phasing there fighter fleet to a three type formation Trainer, light JF17, Medium JF10 would take years as they establish a line and start transition training.I am not an expert on that. But IIRC the Pakistani government is trying to reduce the number of combat platforms to keep costs down. It also wants to build its own equipment. Probably to increase self-reliance and also to reduce costs. That is the likely reason why the J-10 has not been purchased so far despite the Chinese trying to sell it more than once.
It could be that as long as they can get F16 they will prefer it. As it matches the top machines India can field.
But if India gets F21 I almost guarantee a hard push to J10.