Grant's Army trio reformed, concerned with movement of soul (14)

I believe the answer is:

transmigratory

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'concerned with movement of soul' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'grant's army trio reformed' is the wordplay.
'reformed' is an anagram indicator.
'grants'+'army'+'trio'='grantsarmytrio'
'grantsarmytrio' anagrammed gives 'TRANSMIGRATORY'.

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I've seen this clue in the Sydney Morning Herald.

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