Looks similar to: EKF3 Lane Switch - almost a FRIDAY FAIL
and EKF3 switching to DCM and back - #2 by vbnhu
@priseborough says: "The lane selection logic got suckered into a switch to the second IMU EKF by a GPS glitch at 04:54:50. Unfortunately IMU2 had developed a large Y gyro offset before takeoff and was in intermittent bad health which allowed the switch.
This is another example where the user should have been warned by the GCS if the backup EKF is unhealthy."