Applying for PERM

Dear Sir,

My husband is on H1b visa …his 6th year is ending in sep 2016
Currently he is with indian MNC company(planning to quit this company)
now that we are planning to apply for PERM we have few queries which we are hoping to get it clarified:

  1. He got an oppurtunity as FTE in an american company, wanted to check how early he should apply for the PERM since his six years are completing in sep 2016
    2.also we heard that if we go as FTEs then companies take minimum of 6 months to apply PERM,if this is the case is it advisible to join this company as FTE or better to go with desi consulting company
    3.we are also hearing that one should apply for PERM before 365 days of visa expiration (6th year), how do v calculate 6 years, is it petition applied from 1st year to 6th year or first visa/i-94 stamped to 6th year
    4.Also since he has visa stamped till sep 2016, if he visits india before sep 2016 does he need to go for stamping ? if not, do he need to carry any specific document for safe side?

Appreciate your kind response!!!