Avg time these days to receive i797 approval copy after approval.

Hi Friends,

Could any please me. I am on a sticky situation right now. I resigned from my current employer to transfer my h1 and join a employer in US(right now i am in india). H1 transfer (PP) was approved on 16th Sep 14 but my employer hasn’t received approval copy yet.
Any idea how much more time it might take? Any other suggestion?