According to Nomad (I have their Ti band), they say Apple specifications call for SS end links. I don't know if they are making that up, but they are a legitimate company and one of the first to come up with a true Ti bracelet.
In the Faq section:
Titanium Band - 45mm | Natural Hardware | NOMAD®
Built from Grade 2 Titanium and an advanced Diamond-Like Carbon coating, this band is engineered to be as light as possible while giving you the eleganc...nomadgoods.com
I’m pretty sure the factory ends on the ultra band are Ti no?