Sorry, that was not the intention. My English is not perfect and I’m still working on it, so I’m just doing it on the side and I don’t read the whole thing very well.
Or I’m also stupid and I didn’t understand the offered solution.
The offered solution simply creates a timestamp when to fire the notification 14 days in the future and overwrites it whenever the event occurs again.
I think the code that Troon posted is good, the only thing I would change is the trigger for the notification.
Make it a template that triggers on now > helper since this will catch it even in the event of a reboot.