-True.
Does he have to be in US when submitting the renew form?
-Yes.
Can he fill out the form and go to Canada and then we mail the form (or he mails it from Canada) for him 120 days before it expires?
-No. He only needs to apply for AP, not need EAD. He needs to have approved AP to travel. If he needs to leave earlier/urgently before the AP approval, he may just go to the local USCIS office to see whether he can get the emergency AP.
Also does he need to redo finger print when renewing the AP/EAD combo card? He did his finger print in May.
-Not need it.