Regarding travelling with 4 months valid H1B visa

Here is the scenario in my case:

  1. Valid petition ending 19 Sep 2016
  2. Got the H1B visa stamped in Aug 2015 and visa is valid till 19 Sep 2016.
  3. Never traveled on this visa yet. I am planning to travel by 05 May 2016.

My question are:

  1. Would there by any issue in my case at the port of entry?
  2. What is the minimum validity required for traveling on H1B visa, especially when I have never traveled on that visa?
  3. When should my employer apply for the extension?
  1. No

  2. nothing like that as long as you have valid reasons

  3. in general 3 mnths before expiry

Extension can be applied even in the last month. As long as you have validity, there will not be any problem.