It depends, if you need Cubase Pro 11 now, or you can wait.
If you can wait, of course, you can buy the license now and wait for the code activation once the next version (Cubase 11.5/12) is released. Then you will get license of the very latest Cubase version (11.5/12).
With Cubase 11.5/12 license, you can start Cubase 11 or Cubase 10.5 or Cubase 10. So if you are afraid of getting very fresh version (if you are afraid of the new bugs of the new version), you can install and use any older Cubase version with the license. This is of course true for Cubase 11, so with Cubase 11, you can start Cubase 10.5, Cubase 10, etc.