Cirrus modem LTE not stable in 4.3.7 (AP1300) - Quectel

I saw some threads about the same issue, but none are resolutive.
I have EP06ELAR03A08M4G modem (Quectel) pre-installed in the AP1300.
After updating to 4.3.7 the connection sometimes drops for hours and then comes back.
This is annoying, since I control this modem remotely from a different city. The modem only has LTE connection (no backup) and it is used to provide internet access to IoT devices and IP cams for survelliance.
I tried set QCM, QMI, different APN settings but the issue is still the same.
Any chance to stabilize it ? It’s a problem for me to get it back to 3.x for now…since I live 500 miles away from that city.

Any hint is appreciated.

Thanks a lot for your help,

I forgot to mention that with the same configuration and same sim/operator using 3.217 the modem connection works perfectly without any disconnection.

You have installed the snapshot version 01.01.2024 or the beta? Maybe wait for next snapshots, perhaps will be better. Just in case to save a long trip which for sure will solve your issue.