Sinful bent Her Maj managed around end of July (7)

I believe the answer is:

errancy

'sinful bent' is the definition.
(tendency to sin or err)

'her maj managed around end of july' is the wordplay.
'her maj' becomes 'ER' (Elizabeth Regina ie Her Majesty Queen Elizabeth).
'managed' becomes 'ran' (both can mean organised or was in charge of).
'around' becomes 'c' (abbreviation for 'circa').
'end of' says to take the final letters.
The last letter of 'july' is 'y'.
'er'+'ran'+'c'+'y'='ERRANCY'

I've seen this clue in The Independent.

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