Unstable WAN connectivity (5G home internet) causing opnsense crashes

[TheLinuxGuy]

I've been using OPNsense for several years, the product is great and has been rock solid for Cable modem ISPs. Several months ago I switched to a fully wireless 5G home internet ISP (T-mobile) which seems to be causing opnsense to randomly crash and services to stop working.

The pattern I have observed is the following:
- internet on LAN and other VLANs stop working completely
- opnsense Web UI indicates a crash and to report it (not super helpful - but have done several reports already)
- opnsense dashboard shows the following services as stopped or failed:
* Unbound DNS
* flowd_aggregate
* My OpenVPN clients are down
* All my gateway monitors are 'offline'

Sometimes restarting unbound is enough to bring everything back online - but that is only 1 out of 4 times. Most times I have to do a full reboot of opnsense to get things back online. I had tried to do 'reset' WAN interface from the interface status menus to no avail.

While I admit that my setup may be complex since I run opnsense as a VM on proxmox and then WAN connectivity to ISP equipment is connected directly to proxmox host to a bridge interface I use for clients I want to be directly connected to ISP.

Has anyone experienced or is it well known that if a WAN connection may be unstable there is odd behavior in opnsense to be expected?

To be clear, I have noticed the issue to be the ISP equipment (Nokia fastmile 5G router) which even when directly connected to it there are 'brief connection interruptions' of sometimes 30 seconds to a few minutes while the modem reconnects to other LTE/5G cell towers. But I would expect opnsense to be able to recover from this without a reboot - or perhaps I am missing something?

Restarting downed services do not fix this, restarting WAN interface via web UI does not fix it either. opnsense does get an IP but somehow its routing table to the internet just doesn't work until a reboot occurs.