Hi! First-time poster!
At the moment, it appears that a component can only be associated with one group. It would be useful if a component could belong to multiple groups. Here's a use case scenario:
Consider three subdomains a.domain.com, b.domain.com, and c.domain.com that share a common primary link. The link is a single point of failure.
Under Statuspage, I'd define the subdomains as component groups and the link as a component associated with each group. If the link went down, I'd update the link component status to reflect this and the status of all three subdomains would automatically show as down. It doesn't appear to be possible to do this at present in Statuspage.