That's good to know, and annoying, but also a little confusing.
The page you linked indicates that a bot will comment on the PR. I am looking at https://github.com/microsoft/calculator/pull/553, but I do not see any bot-generated comments, other than the "All CLA requirements met." status line you mentioned; and I do not see a "cla-signed" or a "cla-not-required" tag on the PR.
Still annoying, regardless.