I lost my bump stops, and that coupled with the rear shocks being on the way too meant that I kept bottoming out into the wheel arches. That caused the tyres to wear unevenly so consequently needed to get two new rears. Could have saved myself 200 quid if I'd addressed it sooner.
Just to follow up: I couldn't get any new ones in time for the MOT so I took the old ones out. It passed with no advisories. I will put some more in soon though, because I don't like the thought of the springs bottoming out at speed.
I swung the spring pan down for the first one, but it was such a pain getting it back I just sliced the second bump stop in half with a coping saw and pulled the two bits through the coils.