Is there a way to stop using emails for new accounts, but continue for existing?

Hi, all. :)
My question has to do with emails.
I want to update and get some new ones, as the ones I have are on a few lists.
Sven said all I have to do is uncheck them and add new and the unchecked ones will still be used to verify etc. for targets that are halfway through the process of posting and the new (checked) emails will be used for new accounts.
Will I still be able to post additional links on existing accounts if the emails that were used at the time are present but unchecked?
I want the benefit of clean emails, but I also want to begin posting additional links where possible.
If not, I guess I can just create a new project with the new emails, and continue using the old ones to post on the old projects.