The default iOS Calendar app sets a notification trigger and its timestamp appear in the UI as "in x min".
Please refer to the screenshot below.
Is that a private API Apple uses or an open one?


The default iOS Calendar app sets a notification trigger and its timestamp appear in the UI as "in x min".
Please refer to the screenshot below.
Is that a private API Apple uses or an open one?


This functionality is not publicly available.
All remote and local notifications created by a third-party application have a timestamp that shows the date when the notification was being displayed for the first time. This means that it's not possible to have a future date for the timestamp.