(Multiple list consolidation) Excluding profiles that might opt-in later

Hi folks, 

So I’ve taken on some accounts where each has a “Newsletter” list, used for the typical default shopify integration plus a bunch of other ones created for various purposes. 

I’m consolidating them into a master list, and my thoughts were to create custom properties for the profiles in each of these “original” lists such as“Newsletters”, “Wholesalers” etc.

One of these will also be ”Exclude From” = “All EDMs”. The reason being that there are multiple people in the organisation still using the lists for different purposes. Until the process of adding and emailing profiles is streamlined for everyone (and they’re not being actively added to) I’m leaving them as-is, but incorporating everyone else into the master.

I will end up with a segment of profiles who have the custom property “Exclude From” = “All EDMs”.

I’ve got a segment of these profiles that I exclude from newsletters, and my question is: If later via some outreach these profiles decide they now want to receive newsletters and they click a link or button that updates their profile with the property “Content Preferences” = “Newsletters”, how do I stop them from remaining excluded? They will have criteria that is typically in both the include and exclude sections. 

Hope this makes sense, thanks!