I've written a letter explaining the whole situation (including how I've been ignored).
I've always found that letters are much more effective than phone calls for getting stuff done, hopefully that works
Thanks for the advice.
Good news is that I now have a SuperHub 3 and have all the downstream channels I should.
It's funny, last time I had this router years ago I had to fight and fight to get them to give me the SuperHub 2AC back. It seems they've sorted most of the reliability issues now though.