Yes - your old Opt-Out Link will remain functioning.  Once Opt-Out Links are deployed using the new domains, we will keep the existing Opt-Out Links active.

*Please note - as noted above we will never disable old Opt-Out Links.  However, if you delete an Opt-Out List, delete the domain, or change the CNAME from the system default domain, the old Opt-Out Links will remain functional. 

To learn more about the benefits of adding Opt-Out Domains in SUPPRESS, please review this article: How to Add an OPTIZMO Managed Domain & IP Address

If you have further questions, please contact us: support@optizmo.com