Fruit that won't give a fixed delivery time? (4,4)

'fruit that won't give a' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'fixed delivery time?' is the wordplay.
I cannot quite see how this works, but
'fixed' could be 'firm' (I've seen this before) and 'firm' is found within the answer.
'time?' could be 'date' (date is a kind of time) and 'date' is found in the answer.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).

Can you help me to learn more?