How to Convert Date-Times using Prevailing Timezones

Questions
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2

I think a better approach would be to use the built-in timezone-related functions. For example, using your Unix moment of 1652439989, we can find the timezone offset at that moment:

TimeZoneOffset["America/Chicago", "GMT", FromUnixTime[1652439989]]
(* -5. *)

You can convert to that offset:

TimeZoneConvert[FromUnixTime[1652439989], TimeZoneOffset["America/Chicago", "GMT", FromUnixTime[1652439989]]]

You can also just do this with an option in FromUnixTime:

FromUnixTime[1652439989, TimeZone -> TimeZoneOffset["America/Chicago", "GMT", FromUnixTime[1652439989]]]
3

Thank you Eric, this is the function to use to convert dates with prevailing timezone (offset). Problem solved.