When I did a mock booking including AMS, it mentioned lounge access at Man but not for JER.
Must be some sort of system bug again.
Sure I've seen the odd post where people have been refused though.
Did play around with a MAN-JER-MAN booking including a hotel stay and it wouldn't book the MAN-London sectors into anything but J (added well over £200 to the normal price) and I bet that wouldn't cause any problems.