You are not doing anything wrong
it is the way the thing works.
And that is not how I (or you) would want it.

I pointed the developpers allready to this problem, and they will take it in consideration.

It's not that easy to let execute somethingin the future if the site is not running at that time.
So they will come with something, I'm sure of it..

For the moment, you can't do anything else.

Thanks for your answer.
Perhaps there is a way to explore :
The article appears online (issue date at 11pm), when the first reader is going to look at it, it makes a hit on server, which could be used to launch the email notification...

I agree this is a problem to do something without any activity on the web. There is 'cron command' too but i don't know how this can be done with php.

I will wait, hoping developpers will find something soon.