The Blue Ocean Acceptance Tests, when run against a version of core >= 2.128, will fail to login correctly, causing many tests to time out. That's because the new button says "Submit" and the old button says "log in". The exact line where we time out is this one.
We haven't seen this until now, because the "default" in Blue Ocean's ATH runner script, is set to 2.121.1.
A simple if/else to check for the style of login, and act accordingly, should do the trick.