The most common and most likely answer to this crossword clue is the 3 plus 2 plus 9 letter word DAY OF RECKONING
I've seen this crossword clue in The Times
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More clues leading to the result DAY OF RECKONING
- When to pay for past 24 hours of audit?
- Summer’s end?
- A lot of calculation when called to account
- Find a cry gone, OK? Possibly, when justice finally triumphs
- Agony for Dickens, almost broke when ultimate account’s due
- Time to face up to past requiring treasurer’s attention?
- When you have to render up accounts...
Buddy explains!
The straight part
We know that "Summer’s end" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case summer’s end = day of reckoning.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.