...and for the flight back, indulge yourself again (7)
I believe the answer is:
retreat
'and for the flight back indulge yourself' is the definition.
I can't tell whether this defines the answer.
'again' is the wordplay.
I cannot quite see how this works, but
'again' could be 're' (prefix meaning 'again') and 're' is found within the answer.
The remaining letters 'treat' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for retreat that I've seen before include "withdrawal" , "place for meditation" , "The Priory, say" , "What cowards might do" , "asylum" .)