I'm just making a fix available for a big I encountered on the RUT955 GPS settings. If you want support enabled for every satellite constellation (Galileo, Glonass, and Beidou), ticking them via the web interface is ignored. If you `cat /dev/ttyUSB1' you see only GPS sentences are output. To fix (and enable every constellation for example) you need to have the boxes ticked, and also run the following once to enable them on the GPS receiver:
gsmctl -A AT+QGPSCFG=\"glonassnmeatype\",7
gsmctl -A AT+QGPSCFG=\"galileonmeatype\",1
gsmctl -A AT+QGPSCFG=\"beidounmeatype\",3
reboot
To test, simply:
cat /dev/ttyUSB1
...and you should see messages starting with GN, GL, PQ, and GA.