iMac Pro Mojave/Big Sur panic-ing with regularity with NordVPN at in_pcb.c

I get NordVPN panic-ing my Mac ever since Mojave and even with Big Sur (latest 11.1) always at the same spot each time :-

panic(cpu 0 caller 0xffffff801f4bf121): assertion failed: ifp->if_sndbyte_total >= len, file: /AppleInternal/BuildRoot/Library/Caches/com.apple.xbs/Sources/xnu/xnu-7195.60.75/bsd/netinet/in_pcb.c, line: 3937

Whist I understand that the panic point symptomatic with the root cause elsewhere leading to that panic point, in this case it's always at the same in_pcb.c and either on the 3937 line or very close to it. It happens approx 70% of the time after starting up NordVPN. Prior to the panic, the whole system is non-responsive.

I've tried other VPNs (OpenVPN accessing NordVPN connection details) and it works fine so I do have a workaround. But I've consistently had this problem with NordVPN for the past 8+ months ever since Mojave. Further, since it's been happening so long already, if you were to ask me to uninstall the most recent installation causing this problem, I wouldn't even know what to uninstall.

Also just for my understanding (old school UNIX SA here), I believe MacOS is a preemptive multitasking OS, where in theory the kernel space is protected from the user space; unless there's a badly written driver in the kernel space. Is this what's happening here??

I've saved up quite a few of the panics over the period and happy to share if anyone can help me troubleshoot what was causing NordVPN to be able to crash my iMac Pro. And yes each time it crashes I send the report to Apple.

Cheers