"my support Profile"
I've always been able to view My Support Profile via Apple Support . That's where I would keep track of all my apple device including airport express, apple tv as well as my IOS devices.
Last time I looked was Oct 2016.
Just spoke with apple support and after advising me to try the supportprofile.apple.com - which yielded a message "this page has moved" H e agreed he can't find where it went and suggested I talk to customer
iMac (21.5-inch Mid 2011), OS X El Capitan (10.11.6)