Simpsonjos,
As per my understanding, your h1b can be reinstated within 6 years from your visa expiry date. I'm not sure if petition expiry date counts as visa expiry date. In all probability, you can keep it as 6 years from your last day in US. I know for sure it's six years, but not sure of from which date (visa or petition or departure date).
And let me throw some light on gc wait times. There are nearly 2.5 lac people from India ahead of someone who is filling their gc today in eb2. eb2 India gets only 2800 gc s per year and that number should accomodate dependent of those two lac applicants . Do the math and figure out when your gc might come . From 2009, the volume of applications are enormously high, and it is crazy after 2011. So it's no more five year, eight year, ten year deal as it used to be. Unless some reform comes, Indians can never get gc in their lifetime. Worst part here is that neither trump nor Hillary or any politicians for that matter have any plans to fix this mess as it's just affecting only one country. You might want to read this
http://immigrationgirl.com/what-is-the-real-wait-time-for-eb-2-india-82-5-years/
I went through your situation in previous posts. With ageing out kids, you should move to Canada or India no sooner. Else they would be in a limbo w.r.t education, culture etc. You may never be able to get gc in next 20-30 years with present system. They cannot work part time, cannot get student loans, get in state fees, get scholarships, get opt on h4 visa. They need to switch to f1 to get opt, but they still cannot get other things. Above all they need to go through h1 lottery process and stand in same gc queue where you are standing . All these would be fine if they come from India, but they would feel bad if they do their schooling in US and join college.. seeing their friends getting everything. By you not moving, you are denying them a potential opportunity to settle peacefully in a peaceful developed country. Please make a move soon to Canada without thinking much about coming back to US. Canada is a developed country too, and except for salary /job front, I'd presume it just as another US state.