My wife just started her F1 OPT and we just got to know that she is pregnant. I am currently on H1B and has my I-140 approved. We are thinking about changing her to H4 EAD. Looking at the current processing time for F1 to H4 it can take more than 1 year. If we apply for H4 now can we apply for 2 year F1 OPT extension incase H4 takes longer than 1 year?