1.9.x was the development (aka "mainline") branch and 1.8.x was "stable". Odd-numbered releases directly become the next stable. See the graphic here: https://

1.9.x was the development (aka "mainline") branch and 1.8.x was "stable". Odd-numbered releases directly become the next stable. See the graphic here: https://www.nginx.com/blog/nginx-1-10-1-11-released/ https://www.nginx.com/blog/nginx-1-10-1-11-released/