Well, I think we have tried everything we can, and I am all out of time.
Her indoors is demanding a resolution, and so I have purchased some powerline adaptors to enable her to plug into the network from wherever she is in the house.
It's not ideal but it is a solution.
Hopefully in the fullness of time the new kernel will be released and the Toshiba's wi-fi will work again.
I would like to thank you all for your help.