Total Github failure

Today I clicked Update Cutenews from the control panel, was shown a list of files to be updated - all green and writable, red files indicating files that did not exist in my installation and presumably would be added during the update.

Click.

After about 30 seconds - Page Cannot Be Displayed error

Reopening the browser and what do I find
  -a Github page has replaced the Cutenews installation index page that redirects to a Github 404 error page.
  - deleting the index pasge and replacing it with the original does nothing. Trying to access my Cutenews installation
     just throws up the same error page.

There is no reference at all on the Github page to Cutenews. There is a search box but when used throws a page cannot be found error.

I am a registered user of your product.

What is going on here?