Ruling about turning up is distasteful (9)
I believe the answer is:
repugnant
'distasteful' is the definition.
(I've seen this before)
'ruling about turning up' is the wordplay.
'ruling' becomes 'regnant' (as in a queen regnant, a queen who rules by birth).
'about' is an insertion indicator.
'turning' indicates anagramming the letters.
'up' is an anagram of 'pu'.
'regnant' going around 'pu' is 'REPUGNANT'.
'is' acts as a link.
(Other definitions for repugnant that I've seen before include "Unacceptable" , "Disgusting" , "vile" , "Loathsome" , "Nasty" .)