Hmmmm..fingers crossed it's OK now.
I was happy with the lens I bought.
I am very disappointed that after six months and after using Quidco's claim process, Jessops declined to pay out, claiming I had either cancelled or returned the item. This was not true.I have been happily using my lens for the last six months.
I felt conned and a bit cross so I e-mailed Jessops direct (the CEO actually - found him by googling), with a copy of the order and told them how disappointed I was.
Very surprised and pleased to get a phone call from their customer services, who explained that at some point the online order had been revised by them for some reason I didn't quite understand. However, they agreed to refund the cashback to my card in the next few days.
So hopefully an annoying situation has been resolved.
Edit: Promised cash back has now been received - well done them!