Word has come to me via the TimeNuts mailing list that certain models of SkyTraq GPS receiver may have firmware issues that prevent them from getting a fix due to recent changes in the GPS almanac. This same note said that modules in survey-and-position-hold mode do not suffer from this problem. All of the SkyTraq modules I have obtained are in this latter category and (so far as I can tell) are continuing to operate normally. I have inquired of SkyTraq if there is any field remediation that should be taken, and I'll update here with anything I get back.

Any GPSDO with a 6 pin diagnostic port can be connected to a TTL level serial interface. Presumably any remediation software that might come from SkyTraq would operate over this interface (if a field remediation is possible at all). A GPSDO with a 4 pin diagnostic port can also be similarly connected, as long as the microcontroller on the board is held in RESET (tie pin 5 of the ISP header to ground).