It says "I'm still on {0}!" when joining a server under the current version.

• Minecraft 18w14b -------------------------------------
  Was this messed up? I don't understand...
  So it says "Oudated server! I'm still on {0}

  "

..is this a bug or is this version in development still?
THIS BUG IS STILL NOT FIXED
Java minecraft running on a Windows 10 PC.