VO2Max: "No trend", probably also resulting in wrong training status?

For the last couple of days the beautiful new feature of VO2 Max trend displays nothing. No line, "No trend" in the summary page. VO2Max itself seems to update from Edge 530 fine. It might be the reason why my F7 shows Training Status as "Recovery" while Edge shows "Productive". Has anyone experienced something like this lately?

Edit: OK - I've got one theory - Fenix started to use running VO2 Max suddenly (which is weird, since with a broken 5th metatarsal I had been barely walking, let alone running for the last two months). I can't see how a reading of non-cycling VO2 max could even be obtained and in a situation where my only fitness activity is on wheels.