Spectra just (Tuesday Morning 8 October 2019) released this update notice for users of Legacy Spectra and Ashtech equipment:
 
Legacy Spectra Geospatial GNSS Receiver Firmware Upgrades
Recently, we have received some reports of positioning issues with Spectra Geospatial legacy receivers encountering an inability to report a position. This is caused by the GLONASS almanac providing some out-of-tolerance data for one of the GLONASS satellites, and the positioning engine in the receiver treating the almanac as accurate.
This issue has been resolved with firmware fixes which you can download through the links below. This should be distributed immediately to all affected users, as it will resolve the issue with the GLONASS almanac.
In addition to the above, we have received some reports of positioning issues with the ProMark 500. We are currently developing a fix for the ProMark 500, and should have a fix available soon.
 
In addition to the Spectra location, I have mirrored the firmware at this web location for users who have difficulties getting the downloads:
 
  https://ashgps.com/2/2019GloUpdates/index.htm
 
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Good Mapping and Surveying to You All!
 
Mark Silver
ms@igage.com
iGage Mapping Corporation, Salt Lake City Utah
+1-801-412-0011 x16