That from Yvonne periodically (3)

I believe the answer is:

yon

'that' is the definition.
(archaic term meaning 'that')

'yvonne periodically' is the wordplay.
'periodically' indicates alternate letters (letters must be selected 'every so often').
The alternate letters of 'yvonne' are 'YON'.

'from' acts as a link.

(Another definition for yon that I've seen is " Those Scots".)

I've seen this clue in The Times.

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