Thanks Jussi, this is really helpful!
For the FW upgrade, thanks for clarifying, I think I would stick to the one I've for now until I'm fully satisfied which is not too far away based on the recent performances.
Yes I think your diagnoses are correct for the messed-up Pos. Hold I experience with poor GPS reception. It is very clear that among 4-5 flights, 2 were astonishingly stable and GPS HACC in both is =< 0.5 m.
So do you think I should go for another dance?
viewtopic.php?f=35&t=2852 (Last 009, is the current log used in calcs)
Baro is nicely covered - I don't think that's an issue.