I know how to add from the web portal, but this particular provisioning profile is marked as "Managed by Xcode", therefore, I need to either stop managing from xcode or add a UDID into the profile from Xcode.
I cannot find any way to "stop managing" in Xcode.
In Xcode, I know how to add the device by tethering to my laptop and refreshing, but I don't see any option to add a UDID.
Here is what worked (multiple times now) ...
Voila!