Last night I have a problem after meridian flip: the mount doesn't started tracking and I have nice startrails subs. I have tried to analyze the logs, unfortunately I don't understand them. Can someone please help me to analyze the log?I have trimmed the log to contain only records between last successful capture and first failed one.

I am no expert with the logs but it looks like Mount is tracking Sidereal after flip
[2023-08-24T00:25:07.765 CEST INFO ][ org.kde.kstars.indi] - EQMod Mount : "[INFO] Telescope slew is complete. Tracking TRACK_SIDEREAL... "
[2023-08-24T00:25:08.635 CEST INFO ][ org.kde.kstars.ekos.mount] - "Meridian flip completed OK."
Guiding seems to be OK otherwise the capture would have aborted..

So the only other suspect I can think of is the guiding parameters checks are not correct for a 600s exposure.

Thanks AstroMuni, I also don't see any problematic behavior in the log. What I have done differently is that the first part of the night, before flip, guiding reused saved calibration. Once I seen that it is using it, I have changed the setting to be sure that after flip it will calibrate. And this could be the root cause. I am going to capture also this night, so I will check what will happen after flip, and I will not disable the calibration reuse.