Omnibus F4 Pro V2 running ArduPlane V3.10.0-dev (9cd62e81) works OK with MP 1.3.58, but gives EKF errors with MP 1.3.59. Proved the fault by downgrading to MP 1.3.58. I will look for the appropriate forum to log the issue.
Issue #1990 logged in GITHUB against Mission Planner