How do I schedule a mailing to run in a couple of hours time with the CiviCRM API?
Can you double check if the other mailings have the same time in the database and in the UI? It's quite common that one or the other is not taking into account the same timezone, ie if your UI is assuming your database at GTM and your user is at GMT+2, it's normal it starts right away (or the other way around, timezones are always confusing ;)

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