One-time schedule

on date @time

Parameters

date: Expressed in yyyy/mm/dd format and must be in the future. A date specified is affected by the timezone in question.
time: Expressed using a 24-hour clock format, HH:mm[:ss] (where seconds are optional) and must be in the future. The time you specify is affected by the timezone in question. For example, a user is in Chicago (CST) at 10:00 on 12/18/2020 and tries to make a schedule for America/New_York on 12/18/2020 @10:30. This will not work because the time specifed is already in the past.

for America/Chicago on 2018/08/01 @08:00: Schedule set to run on August 1, 2018 in the America/Chicago timezone at 0800 hours.
on 2018/09/10 @14:30:30: Schedule set to run September 10, 2018 in the timezone in which the server is located at 1430 hours and 30 seconds.