Thanks for your interest in our Solution! Answers inline -
I’d like to put the guests on one subnet, the admin staff on another.
–On current firmwware, the Balance 20 does support VLANs which would allow you to setup as outlined. More information can be found here
Give the Admin Staff priority, ie they always get at least 20% of the capacity.
–Current firmware allows you to setup User Groups to designate Bandwidth on the IP/User level. More info here
If the main Cable goes down, failover to Wireless 4G to the Admin Staff Only.
–Absolutely, Outbound Policy allows you to setup a number of LAN-to-Internet traffic rules a number of ways. More here
The way we keep the separate SSIDs working is to use VLANs, each VLAN has its own subnet and inter VLAN router is customised depending on the customer requirements. This rule succeeds to block the Wi-Fi from accessing the customers backup LTE as the Source network matches the VLANs subnet assigned to the Guest Wi-Fi
You may like to have a look at this previous thread
Also there is a guide here that may be useful
If you are still having issues, PM us your contact details and supplier, we will help get this sorted for you with the local team.
Happy to Help,