How much time do I have to convert my wife F2 to H4?

USA H1B Visa
1

HI there,

I was on F1 OPT this week I received my H1B approval. now I have to change COS for my wife F2 to H4.

  1. Can apply from here because for me status has been change from Oct 1 2017, is there a time frame when can Iapply for my wife COS?

  2. My employer told me to send her back to india to get H4 visa?

I am so confuse now what should I do?

Please let me know.