Ken, can you have a look at this, starting from 02:52. Luckily I woke up around 3:00 o’clock and found that SGP is not imaging, but in this dither/settle/frame restart endless loop with PHD. The guide star was there and PHD did settle every time, but then dither command sent again and I think maybe dither himself was accepted as star loss/drift, so it restart the frame, dither again and back in the loop. Frame restart distance reported almost always the same, 3.2 or 3.1, 3.3 pixels.
I watched it for another couple of minutes but this didn’t solved by it self, I aborted the sequence and restarted and all went fine from that point.
SGP log : Dropbox - File Deleted
PHD log : Dropbox - File Deleted
The guide star was only reported as lost one time. That certainly didn’t help matters, but that was not the cyclical issue you observed.
Somehow, your guider error tolerance for frame restart was set very low (0.6 pixels). The guider reported values above this A LOT and, as a result, continually restarted your frames.