delaying the move to the usa

I am a Canadian citizen living in Canada and working in the US for an American company. I work as an American consulting company and spend 4 days in the US and fly back home on Thursdays for the weekend. I just got an email from my company indicating my PERM got approved (I was on an H1b and they did the sponsoring). Given some family obligations I would like to ideally stay in Canada for 2 years and move to the US in June of 2019. Is there any way I can do this without jeopardizing the GC status? From what I gather, it takes about a year to get your GC from the time you apply for I-140 and you have 6 months to move to the US from the day you get your GC- Is this accurate? Also, If it makes any difference, I have a property in the US, have US bank accounts, and work for a US company as mentioned earlier. My wife and kids however are rooted to Canada. Any suggestions would be much appreciated.