It is clearly not all planes were disassembled and checked, from what I read it is not a routine check so it will take a while until all planes are checked. So

It is clearly not all planes were disassembled and checked, from what I read it is not a routine check so it will take a while until all planes are checked. So yeah they may have found only 2 more planes with cracks because they only checked 2 more planes that were already disassembled.