I had an incident last night where SGP went into recovery mode when resuming guiding after a meridian flip. According to the SGP log, SGP thought that PHD2 had lost the guide star:
[5/14/2015 12:53:35 AM] [DEBUG] [Sequence Thread] Recovering the sequence (and the auto guider lost the guide star)
but the PHD2 logs shows no indication of any loss of the guide star at that time, but they do show show phd2 sucessfully locating a star and guiding.
Here are the logs: http://adgsoftware.com/misc/sgp_2015-05-13.zip