Hi James,
Many thanks for all of your advice, except to retire the Surface. Pleased to report that it has recovered operability, has updated completely and is working fine.
Although I have been retired for 22 years, retirement didn’t mean that I became a paperweight (burden) and I was determined to resuscitate the Surface.
Appears that all the problems related to the wrong instructions on the video on this Microsoft web page: https://support.microsoft.com/en-us/help/4023512/surface-creating-and-using-a-usb-recovery-drive#Download . I had tried recreating the Recovery Drive exactly as per their instructions (3 times in all) and none of them worked.
After your last message, I eliminated the step “create a recovery drive” (as at 55 seconds of the video) and just quick formatted the USB Flash Drive and extracted all the files directly to it as you advised.
It didn’t work at first but on the 4^th^ attempt it did and took about an hour to reset.
Initially it also allowed updating but after 2 very large update cycles it stopped yet again. The 3^rd^ time, I left it trying to update for over 24 hours. Eventually after even more extensive browsing found several articles about requiring KB3173424 and KB3172614. Downloaded and installed them and they broke the “no update” spell. After several further very large updates, it now appears that the Surface is completely up to date . . . more importantly I have the Start Menu back.
Many thanks again.