Hi,
My 2004 XK8 had the rear sensors in the rear bumper, colour matched but very visible.
I can only think of two things.
1) You have an aftermarket reversing sensor.
2) Stratstone ticked a box but didn't actually check it.
The only other possibility is that your car has had a new (older) rear bumper fitted since Stratstone checked it which didn't have the sensor holes and the sensors were 'omitted' ....But I can't imagine you would not have known about that!
Should keep you busy over the bank holiday weekend.
