thought I'd post an update to the situation.
Emailed Billion to get a copy of the firmware as there isn't on on their site. Billion confirmed there were no further updates to the version I had and sent the firmware.
On Monday morning I did a factory reset, firmware re-flash, factory reset, ran the setup config to enter the ISP details, changed Lan range and DHCP LAN scope, setup Wireless.
All seems fine now