Delay reversed support (6)
I believe the answer is:
uphold
'support' is the definition.
(I know that uphold has the is a more specific form of the action support)
'delay reversed' is the wordplay.
I cannot really see how this works, but
'delay' could be 'hold' (synonyms) and 'hold' is found within the answer.
The remaining letters 'up' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for uphold that I've seen before include "Of appeal court, endorse earlier decision" , "Support, maintain" , "Confirm or support, say a verdict" , "'Support, the law say (6)'" , "'Support, a court decision, say (6)'" .)