I haven't been getting charged as Barclays cancelled the agreement but it still asks for serial/IMEA. It seems that when you return your phone, it doesn't cancel the IUP.Uh... have you been getting charged for it this entire year?
When you try and get a new phone it asks you if you want to enroll or if you already are. If you say you already are thats when it asks your for the serial/IMEI. If you say you want to enroll it doesnt
I'll have to get in contact with Apple but I've a feeling they'll point me towards the retail store.