Never use "usernames" for customer emails
A customer was confused when an old email address is referenced in their "password reset" email. The issue is that the email template says "Hi [username]", which REALLY should be "Hi [first-name]".
In the body, both the username and email address are referenced.
The customer INSISTS that I completely remove the old email address, but I can not because usernames cannot be changed.
The solution I know is to edit the email template (which is annoying in WooCommerce). But the better solution is for WooCommerce to not reference the username in anything that the customer can see.