I work for company from March 2009 under F1 Opt. I got H1B on Oct 2008. Company sponsor for my green card. I just submit i-140 with premium and got approval last week. I suppose to get approval of i-485 within 3-6 weeks.

1. I can change job after I get green card (1 month) but I have heard that it will raise question when I got citizenship. Is there any big problem? I have work for company since 2008. I will it will be enough?

2. In the safe screnario, how long I should work for company after green card? Is that 3 months is enough or it must be 6 months?

What is the problem if I resign too soon? Lost Green card? can't apply for citizenship.