Hi
I only plan to use the HH5 as an additional access point from a pfSense firewall.
I defaulted the HH5 and tried it again. Same settings, Same IP I used last time.. but this time it worked.
Not sure if the reset/default helped or not, but its sorted 
It might of, when ever I start to see issues I have always done a complete factory reset and then gone through setting everything back up.
Also doing a backup and restore doesn't always work as I found out when I did a backup from my old HH4 Type A and restore it on our new replacement HH4 Type A, it just failed and said it was corrupted.
Anything to-do with IP's on the HH6 / Smart Hub etc is a pain to change without issues popping up.
Like I run our own DHCP Server along with other stuff, so I don't use the DHCP Service that is provided by the Hub, so I disable it, now here is the issue, the start and end addresses need to be valid on the hub even though the DHCP Service is turned off, how screwed up is that.
I have said in other posts that I am due a phone call tomorrow from my case handler at BT so I will enquire where I report issues with the smart hub, because I have found a few, some just cosmetic but some being big issues.
But for Wi-Fi Access Points, yeah, if no joy with the Smart Hub I will being disabling it due to its no better than the Wi-Fi on the HH4, and I will be using both of my HH4 and my FRITZ!Box as access points throughout our home, with the same SSID and password, but all using different channels.
Paul
BTBroadband - Infinity 4 - 310Mbps (down), 31Mbps (up)
TBB Speedtest