Email only but publish at later date

I’ve had a look and can’t find a simple solution, so I wondered if it was possible.

Is it possible to Send an Email without Publishing and then to publish the post/email to the site at a later date?

Updating the post seems possible, but I can’t figure out a way to publish post as a standard post once it has been sent as email only.

May I ask what specific use case are your trying to solve with this approach?