Public Service Announcement: If your brake rotor looks like this it is not a good sign:
You can also play "spot the messed up wheel spacer"
Yeah, not good. But it's back together after a little
incident and mobile just about. The new rotor seems a little close to the caliper on that side, but am hoping it's just me being paranoid and not the wheel bearing going. There doesn't seem to be any movement in the wheel so will drive around with it and see how long it takes for something else to fall off.