Both via the API and in the cloud console when I try to access a specific topic in messaging, I get a 524 error.
The list only has 24 subscribers, so I think somewhere a bug has occured.
TL;DR
Developers unable to access specific topics in messaging due to a 524 error. Requesting console error check, network logs, and project ID to investigate further. Bug suspected with only 24 subscribers in the list.