It's a mediocre article. It glosses a bunch of history adequately and then points out a completely different anomaly. By "completely different" I mean "has all the signatures of an instrumental or analysis artefact." It's intermittent (huge red flag) and while the article doesn't say so (additional red flag) close to the threshold of observation.

There are completely mundane explanations (upper atmosphere models slightly wrong, unaccounted-for EM effects) so while there may be a fundamental cause (gravity is doing something exciting) the odds are that it's a boring effect, just like the superluminal neutrino observations.