Currently F1/F2. Got a job. Going for H1B premium processing. How soon do I have to file change of status for my dependent to H4?
(no OPT card)

Do at the same time when you do yours. Otherwise, it will take several months to get approval for your family.

thanx dhoti_prasad ji for the quick reply.
I guess, what I wanted to know is would she be out of status if I got my H1B application approved? Since I will be on H1 and she will still be in F2. (I am sorry, it sounds confusing. I hope others will be able to make out.)

xtreme2005:
F2 is a dependent visa so is H4. If you change your status from F1 to H1, then the dependent's status has to be changed too. I'm quite certain she'll be out of status if you got H1 just for you. I strongly advise you to do it together. It just costs couple of hundred more.

bijay934 is right. Do it at the same time. It is the normal process that everyone does. It is very easy and effort less process. Just give your documents to your lawyer or employer. It is very simple thing to do at the same time.

xtreme2005 ji -
I am sure you know it, but in case you don't, your spouce can work legally with F2 but NOT with H4 - not sure if this is going to be an issue for you.

I have decided to go ahead with it now. As everybody, I thought it would be the best way to go.
Gaule_hero ji, if the H1 goes well, it won't be my issue but if it does not it will be my issue. Anyhow, could you tell us how you can work legally with F2. If not for me, I am sure others can benefit from this.