H4 to F1 COS taking more than 5 months

[tech4appa]

I filed my change of status from H4 to F1 in May 2013 in Calfornia Service Center. I have already completed 2 Sem in a reputed university in CA on H4, my husband is currently on H1-b and our GC is currently I140 approved. It has been 5+ months but my status is still showing "Initial Review". I have called up USCIS regarding this but they said the background investigation is currently in progress and that is why it is still under "Initial Review"

 

Question --

 

1. Is this delay unusual.

2. What could be my next alternative? Do i need to reply again?

 

Any help is highly appreciated.

 

Thanks