Regulates day in November? On the contrary (5)
I believe the answer is:
tunes
'regulates' is the definition.
(tune can mean to regulate or adjust)
'day in november? on the contrary' is the wordplay.
I cannot really understand how this works, but
'november?' could be 'n' (phonetic alphabet: alpha, bravo, charlie etc.) and 'n' is found within the answer.
'day' could be 'tues' (abbreviation for Tuesday) and 'tues' is found in the remaining letters.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).
(Another definition for tunes that I've seen is " Airs, melodies".)