Have performed a few more tests and this is what I've found:
1. Installed 7.4.22 on my phone (that's in addition to 8.1.6 GP)
2. Recorded a short ride with 7.4.22 and then tried to upload it to Strava. Did Routes > Manage Tracks/Routes, selected my ride > Properties > up arrow & globe icon > STRAVA. I selected "Connect with STRAVA" and it prompted me to login to STRAVA; I did this then STRAVA asked me to authorise access to ORUX; I did. I was then able to select "Upload GPX" from ORUX and the track was uploaded successfully.
3. A day or two later I recorded another track with 7.4.22 and successfully uploaded that to STRAVA without any authentication issues.
4. A day or two later I recorded another track with 8.1.6 GP and had the same STRAVA authentication issue as before.
5. A day or two later I recorded another track with 7.4.22 and successfully uploaded that to STRAVA without any authentication issues.
I can't get to the bottom of this. There seems to be a particular issue with 8.1.6 and getting the STRAVA authentication to persist; it seems to lose it each time you close Orux, reboot the phone, or whatever. Also, 8.1.6 has never asked me to login to STRAVA, I just get an authentication screen each time I try to upload. No such problems with 7.4.22.
Ho-hum.
1. Installed 7.4.22 on my phone (that's in addition to 8.1.6 GP)
2. Recorded a short ride with 7.4.22 and then tried to upload it to Strava. Did Routes > Manage Tracks/Routes, selected my ride > Properties > up arrow & globe icon > STRAVA. I selected "Connect with STRAVA" and it prompted me to login to STRAVA; I did this then STRAVA asked me to authorise access to ORUX; I did. I was then able to select "Upload GPX" from ORUX and the track was uploaded successfully.
3. A day or two later I recorded another track with 7.4.22 and successfully uploaded that to STRAVA without any authentication issues.
4. A day or two later I recorded another track with 8.1.6 GP and had the same STRAVA authentication issue as before.
5. A day or two later I recorded another track with 7.4.22 and successfully uploaded that to STRAVA without any authentication issues.
I can't get to the bottom of this. There seems to be a particular issue with 8.1.6 and getting the STRAVA authentication to persist; it seems to lose it each time you close Orux, reboot the phone, or whatever. Also, 8.1.6 has never asked me to login to STRAVA, I just get an authentication screen each time I try to upload. No such problems with 7.4.22.
Ho-hum.