Has anyone had any luck with M&S? I'm still waiting for a sizeable Click & Collect order to track after 35 days and am poised to send the missing Avios Form at the end of the week.

Whilst you can't Click & Collect with them, another retailer that has never tracked for me (5 orders) is Boden.

No issues with JL, Lakeland, Vitabiotics and Tesco.