It will take time, because we have 38 buses with a RUT956 and we just finished to migrate on 7.19.4.
We need first test the 7.20.3 version before deploying it.
In this case, no internet access because Mob1 was down for the same reason than this case : RUT956 - restart not autorestart not restoring connection - Networking Solutions - Teltonika Community
Like we show it on the screenshot Mob1 offline, WiFi in Standby mode → No internet access.
When we were on 7.18.3, the both access were online, is was a mix between loadbalancing and no acces 
As I already mentioned, I downloaded the troubleshoot files before restarting it. I could send it if needed.
Other think we show and that does not change between 7.18.4 and 7.19.3, the memory and flash use who increase to the limit (we use SNMP, GPS NMEA (5000 in flash):
- Fresh install :
- SNMP package installed :
- After 3 days :
Could this problem cause such kind of issues ?