As I said - minor annoyance - it is binary, it is quick to reinstall.
I thought pacaur’s flag --needed may sort it, but I am in the middle of a big --devel update so cannot test.
The really annoying packages reinstall after a long compile - but if there is no solution, then I will continue with dumping them It has only happened a few times since I have been using AUR.
:Edit: --needed does indeed work. Updating my aliases now.