Bingo! you are correct once more it worked.
OK, So I have been rebuilding a lot because i have been testing to transfer over a forum from an old server.
How the heck do i get around this problem. I don’t even use let’s encrypt. After the successful install I updated the app.yml file to change the domain and made sure the Lets encrypt template was commented out in the app.yml and rebuilt but that does not help and i get the same problem Redis failure, am I stuck because calling lets encrypt is baked into the installer?