Is userdatadomains.stor active or a backup ?

After a full VPS migration, we encountered and error with forms which were using local SMTP "550 Please turn on SMTP Authentication in your mail client". We figured out the websites were not correctly being viewed as local users on the new machine. We poked around and discovered and suspected the old IP addresses remaining in userdatadomains.stor may be contributing. This led us to find the KB article "How to Rebuild userdata Files". Following those steps corrected the outbound email issue, items in /userdata/ directory and the files userdatadomains and userdatadomains.json were updated accordingly. However, the file userdatadomains.stor still carries the old info. Is this just a backup file or how to fix ?