I believe renewal has to be initiated within 30 days of expiration date. It wasn't so long ago when I could get the whole work permit/residence permit renewed in Suzhou in 24 hours.

I wonder if this new 3 week thing is only for Shanghai or for the entire country? The document they give you in place of your passport is a joke and not worth the hassle of traveling on it so you're essentially stuck in shanghai for 3 weeks.