The dilemma: if a user updates their user account by changing the e-mail, the uc_orders table is not updated. The e-mail they used when they placed the order is still in said table as primary_email. If the admin then sends them an order update notification, it uses the original e-mail placed into uc_orders, aka primary_email. This would be a problem if the user account e-mail were changed for a good reason by the user, e.g. if the original no longer exists or isn't in their control.

Possible Solution 1: Modify the notification module to use the user account e-mail when emailing customers instead of the e-mail in uc_orders. Just use the UID of the order to snag the e-mail from wherever referentially.

Possible Solution 2: Custom module that updates the uc_orders table when a person updates their user account. Using UID, it goes through and finds every order for that person and, if a difference exists, changes the e-mail to the new one.

Final Note: I am such an, dare I say, uber novice when it comes to PHP that I dare not attempt this. But I feel the issue could use a solution and I want to support a patch/update/side-module. I have a site that's about to go live that could really use this feature.

Anyone interested?