Posted on the Ultimate Air facebook page about an hour ago:

Ultimate Air has closed our doors!
We want to thank all our friends, fans and customers for their support over the last almost 8 years!
We will leave this page up for a while so you can reach us when the site closes. Ultimate Air will post information here later where customers with our lifetime warranty regulators can go to get... them repaired if needed!
Thank you again and Happy New Year!
-Brian
Sorry to hear this. I wish Brian all the best of luck in the future