Alcatel Unleashed

It is possible to create 2 Areas for second location, so up to 1600 sets in total. No problem at all. You can have up to 90 ACT shelves.
I don't see any reason to have 2 networked PBXs. Separate licenses, additional limitations and so on. Better to use virtualization with redundancy.

Some info from support. Publication Date: 4 September 2018 Issue: After the installation of Windows 10 Fall Creators Update 1709, it's impossible to use OmniPCX Enterprise PC Installer. Support answer: The Windows 10 OS is not supported anymore for OmniPCX Enterprise PC Installer. The OmniPCX Enterp...

Official answer from support: please note that not all the GD3 editions support the DIP switch, only the ones with USB in the front panel have this DIP switch. Hence, the GA3 boards role cannot be changed to GD3. There is no official document which states that changing the switches can convert GD-3 ...

I am using for ex.: C for queues without any issue for a long time. Restriction exists for monitorable objects like Pilot

Its better to forget about new message adding on VG. Too complicated. Check does exist UA RECORDING license. It will allow to record VG from 403x or 803x phone set or transfer WAV file to OXE using Audio station and activate on GPA2

Do You have email Integration license for 8450FS ?
Taken from real license file:
Email Integration = 1

For RTP between TDM environment (PRA, UA) on rack and VoIP phones or SIP trunking.

OK, but I don't see conflict between GD placement in separate subnet and need to manage static routes. There are 2 different things.

But it is strange. netadmin allows to enter static route, but it seems no way for GD3

It is possible to add static route through netadmin in OXE CS.
How will behave GD3 board? Can we do similar on it?