Cryptic crossword clue
Switching around Greek letter, claiming pens etc 4-6

The most common and most likely answer to this crossword clue is the 11 letter word SWAN-UPPING

I've seen this crossword clue in The Times
S
W
A
N
-
U
P
P
I
N
G

Buddy explains!

The straight part
We know that "claiming pens etc" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case claiming pens etc = swan-upping.
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.

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