As of v3.0.23 reports run in the time zone set on the browser. See Common Report Parameters for details.
Previous Behaviour
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Scheduled reports already had a time zone specified for the time to run and this is used for the time zone when pre-existing scheduled reports run from 3.0.24 23 onwards. Note however that the report itself will now run for that timezone and not UTC which was the previous behaviour. For example, if a report was scheduled to run at 6 AM AEST (UTC +10), after the upgrade the report will run for the AEST (UTC +10) time zone.
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