Hi Playboy,
You got RFE and why you got it? It's pretty much clearly written in your RFE and the necessary steps to taken before it gets delayed. You didnot mention here why did you receive and asking for 'what to do next?' seems little odd questions to us. Please read your RFE twice, thrice, it's written the reason for RFE and the supporting documents USCIS is looking for the RFE. Talk with your company HR and your company lawyer who filed your H1B, and make sure its company's supporting documents that is missing while filing H1B. (I do not know if it's ur first time B1B or H1B estension).

Once you submit all the required documents as needed by USCIS (these documents are critical, it should be exactly the same thing USCIS is looking  for in RFE, OW chances of rejection is high. Pls dont take it otherwise, if not seriously) and submit before the deadline.

As far as premium is concerned, I am pretty sure that once you get RFE, there is no point for applying for the Premium processing (they will not even accept the premium processing after RFE.) . However, once you submit the RFE with all documentation complete and strong covering letter from the employer, you will get approval within the next 2 weeks, maximum of 14 days. So good luck and just prepare documents as asked by USCIS and submit ASAP.