PERM 365 days rule qualification

[_pune]

My PERM application was filed in Sep 2016. My H1b max out happens in June 2017. I do not have any time spent outside US so far during my H1b usage.

I understand that if I do not get a decision by 365 days - Sep 2017 I can apply for an extension on the H1b visa.

My question is -  do all of those 365 days have to be spent in the US. This is what I am thinking of doing - 

Go to India on Mar 1 2017, come back on May 30th 2017. Once I come back, I apply for a 3 month extension on H1B based on the time spent outside. That gets me to September 2017. If i do not get a PERM decision by then I apply for a 1 year extension.

1. Is this legal and feasible in your opinion? Please advice.

2. Can my dependents continue to stay in US while i am out of US between Mar 2017 and May 2017? Their I94 is valid till June 2017.

 

I understand that I can go out of US in June 2017 before my H1B expires and come back when my PERMI-140/H1B is approved. I am trying to avoid having my dependents change their setup in US - school etc.