Re-booting the Home Hub seems to be the cure for a lot of ills, I suspect BTWifi is just another function that gets kicked back to life with a reboot.
I am also not suggesting that anyone in my home is using that number of minutes but correct me if I am wrong, any BT customer could be connected to my router if they were near by. That is correct but it would not be counted towards your 10,000 minutes, it would count towards their own 10,000 minutes. As I and the BT link I posted has already explained, it is user account specific, not Homehub specific. Is there a way to check this? No
I am only quoting what I was told by BT help via 'phone line and the fact remains that a reboot of my router will then enable BTWiFi to work for a while once more.It may well make BTWifi work again but is not because BTWifi on your Homehub stopped because of it exceeding 10,000 minutes of use. Wireless, both the "normal" wireless and BTWifi-Fon on the Homehub can and often does stop broadcasting and a re-boot of the Homehub is generally the first thing to try to get it going again.
It is not unheard of for the BT Customer Service people to be wrong with the information they give out however if it works for you that's all that matters.