End Ptolemy’s shifting movement of eg troops (10)

I believe the answer is:

deployment

I'm a little stuck... Click here to teach me more about this clue!

'movement of eg troops' is the definition.
I can't judge whether this defines the answer.

'end ptolemy's shifting' is the wordplay.
'shifting' is an anagram indicator.
'end'+'ptolemy'='endptolemy'
'endptolemy' anagrammed gives 'DEPLOYMENT'.

Can you help me to learn more?

(Other definitions for deployment that I've seen before include "Distribution of resources" , "Military action" .)

I've seen this clue in The Times.

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