Staff coming around, but this would require filling (7)
I believe the answer is:
pothole
'this would require filling' is the definition.
The definition suggests a singular noun which matches the answer.
'staff coming around but' is the wordplay.
'staff coming' becomes 'pole' (I've seen this before. I am not sure about the 'coming' bit.**).
'around' means one lot of letters goes inside another.
'but' becomes 'tho' (I've seen this in other clues).
'pole' enclosing 'tho' is 'POTHOLE'.
Can you help me to learn more?
(Other definitions for pothole that I've seen before include "Sorrow" , "Damage to road" , "Water-eroded cave" , "Deep cave; road hazard" , "Deep water-made cave, pit in road" .)