Same issue here, been experiencing serious unstable connection for months. In my situation, the log looks like:

Mon Feb 13 21:53:16 2023 user.info mwan3track[11145]: Lost 4 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:53:34 2023 user.info mwan3track[11145]: Lost 4 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:54:25 2023 user.info mwan3track[11145]: Lost 4 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:55:10 2023 user.info mwan3track[11145]: Lost 3 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:56:08 2023 user.info mwan3track[11145]: Lost 3 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:56:45 2023 user.info mwan3track[11145]: Lost 5 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:57:25 2023 user.notice mwan3[7851]: Execute ifdown event on interface wwan (wlan-sta0)
Mon Feb 13 21:57:26 2023 user.info mwan3track[11145]: Detect ifdown event on interface wwan (wlan-sta0)
Mon Feb 13 21:57:31 2023 user.notice mwan3track[11145]: Interface wwan (wlan-sta0) is offline
Mon Feb 13 21:57:34 2023 user.info mwan3track[11145]: Lost 10 ping(s) on interface wwan (wlan-sta0)
Mon Feb 13 21:57:56 2023 user.info mwan3track[11145]: Lost 1 ping(s) on interface wwan (wlan-sta0)

I tried to lower the fan activation temperature, but no help. The CPU’s temperature never goes beyond 60 C degrees. I flashed other versions of official firmware, and factory-reset it numerous times, still no help. I’ve got the feeling that this one is also having SoC problems like the MT1300 model.