What will happen to H1B visa approval if person on H4 travels to India.

My Wife is on H4 Visa and we applied for her H1B visa this year with the help of one US vendor which got picked up in lottery but we received RFE on 14th September 2017. The Employer said they will send all the required documents to USCIS on 6th December since the Dead Line for receiving all documents was 8th December.

Since the Employer has filed her H1B with Change of Status, what will happen to the H1B petition if she travels to India in the month of Jan and come back by the end of the month in H4 Visa Only, considering, the approval for the H1B visa after RFE document submission may take more time than that.

Could you please help me understand, if she will loose her H1B due to this?