A pie-filling supplier's in dispute (2,4)
I believe the answer is:
'in dispute' is the definition.
'a pie-filling supplier's' is the wordplay.
'pie' becomes 'patty' (patty is a kind of pie).
'filling' indicates the central letters (the letters which fill the word).
'supplier's' becomes 'odds' (I can't explain this - if you can you should give a lot more credence to this answer).
The middle of 'patty' is 't'.
Can you help me to learn more?
(Other definitions for at odds that I've seen before include "At variance (with)" , "In opposition or disagreement" , "In conflict with, oppposed to (2,4)" , "In disagreement or dispute" , "Conflicting (with)" .)