Got i-140 approved. But priority date not current. When is it safe to quit?
Google AC21.
As per new rule of Jan 2017 - stay with the same employer for 6 months for them to not revoke your i140. Check if anything changed
Even if they revoke it, you still don't lose your priority date according to the new rules. You can leave immediately but will have to reapply.
You have to reapply with the new employer no matter what. The benefit of waiting 180 days is to guarantee that you can keep getting H-1B extensions.
180 days