H1b cap exempt

Hi Sir,

I am writing this on behalf of my friend and here is his situation written in first hand, i would like ur suggestion

My previous employer had filed a H1B Nomination in the year 2014-15 and it got picked on may 12th 2015 and subsequently went for stamping on Nov 5 2015 and received a stamped H1B valid from NoV 2015- Aug 2018. However since there were less chances of travel to US from that employer I changed my company this year in July 2016. Now when i look at the status of my petition it says

“Correspondence Was Received And USCIS Is Reviewing It”

Considering this,
I would like to have my queries answered under two scenarios

  1. My current employer B is willing to do the H1 transfer immediately and it would take 2 weeks from now for my immigration team at company B to file for the H1 subject to No Cap since i have not travelled yet. Would there be any hindrance

  2. I am now thinking of Joining employer C in January and they are also willing to file the H1 subject to no cap but considering the documentation etc it would be done in first week of FEB 2017 when the previous H1B would be revoked automatically i suppose. At that juncture would i still be under cap exempt?

  3. How Long does USCIS generally take after receiving the case for withdrawal