Your status depends on your last paycheck.

I know it is tough but it is good to be prepared. You would be out of status if you did not file the applicaton to change status before your last day of your paycheck. Trust me because I went through this painfully. The CIS was asking for the copy of my last paycheck stub.

I was able to transfer to F-2 visa. I know a friend who transferred H-1b to F-1 through community college. You's better contact your local community college or lawyer to avoid the gap.

The best way is finding another job since it will be very hard for you to find a job in the F-1 visa without OPT.