From J-2 to F-1, Thanks

I'm holding J-2 visa now, and want to change it into F-1 visa. My hu*****and's J-1 waiver is still in Pending status, and his contract will end at the end of May.

My question is :
(1) If we get waiver before May(before contract end), can I change status from J-2 to F-1 here without leaving USA? I heard it took 3~4months to get F-1 visa, is it legally for me to stay in USA during waiting period? (My hu*****and's J-1 contract is ended at that time.)
(2) If we get waiver after May(after contract end), is it possible for me to change status from J-2 to F-1 inside USA? I mean, I submit application without J-1 waiver, and then waiting here.

Thank you very much.