[Reiver]

Finally decided to do something about the stonechips on the front bumper.
Undid all the bolts and started to pull the bumper when a metal bracket fell off.

Turned out to be "Insert bumper front Left" (51.11.7.154.715). There wasn't one on the right side of the car (51.11.7.154.716).

Furthermore, there should be a plastic spacer, "Guide for bumper side" (51.11.7.156.555 left) and (556 Right) which is sandwiched between the metal bracket and the frame the bumper attaches too.

Clearly they are not 100% essential but BMW thought they were necessay so I'm planning to replace them.

Too much hassle for the bodyshop to put back in.