Problems with Apple Trade in in the UK

Has anyone had any problems using the official Apple trade in programme in the UK with Brightstar? I wanted to trade in an old macbook, got a quote, had to wait 17 days for the packing details and box to arrive (the quotes are only valid for 14 days). I contacted Brightstar who said they would keep the quotation and order number open. I eventually sent the item back and got a message saying the value had been downgraded - no explanation why... I followed up with them and was told it was downgraded because the item was late. I wrote pointing out that I didn't receive anything from them for 17 days and attached the email correspondence I'd had with them...... silence. Needless to say I have rejected their offer. Shoddy service.