Current appointment changes at midnight (6,4)

I believe the answer is:

todays date

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'changes at midnight' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'current appointment' is the wordplay.
'current' becomes 'todays' (I can't explain this - if you can you should believe this answer much more).
'appointment' becomes 'date' (synonyms).
'todays'+'date'='TODAYS DATE'

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I've seen this clue in The Globe and Mail.

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