CONVERT Modified dates, December 25th 2020 11:15:23 PM AND 12/25/2020 11:15:23 PM, to 2020-12-26T07:15:23Z AND 2020-12-25 23:15:23-08:00, to UTC

AFAIK the file time properties for creation, modification and access are managed by the OS and the OS and its local settings also determine the display format.
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