As a quick followup to all of this, my father is now live with Vodafone. It should have gone live yesterday, but for whatever reason it didn't happen and the internet light was still fluctuating green, rather than solid.
This morning over the phone I had him switch off the router for about 30 seconds, then restart it and do the same with his computer. A few minutes later a browser window popped up, asking him to set his content filter settings and he was able to get started.
The data rate inside the router was pretty much maximum, but his noise levels on the line are quite high and double what I have, however it is working and no dropouts during the day that I know of. Wifi working well across the different rooms.
Tomorrow I'll drive over to check it all and see it for myself. Many thanks for all your help here.
Edited by charlestown (Wed 04-Apr-18 21:17:00)