"my domain" not found on trust.salesforce.com

Having a minor issue. We implemented the mydomain thing (using myco as an example) and now have myco.my.salesforce.com as our domain. All well and fine, however I realized that if we forget/need to verify what instance we're using its not available anywhere.....until I found the box at the top of trust.salesforce.com that allows you to enter your "mydomain" and supposedly will tell you what instance you are using.

Except it doesn't find the domain which is most definitely the one being used successfully in the url. sigh.

Not a super critical thing as I DO remember what instance I'm on....but wondering if this is a bug on the trust page or a specific issue with our custom domain setup. Anyone else notice this?