Not Valid Private Warps no longer have the "zzz-username-" prefix

What I did:
tried to /warp to one of my private warps

What I expected:
i expected it to have zzz-Alfonios- at the start

What happened instead:
the "zzz-username"- prefix had been removed

Where (world and coordinates):
world, plotworld, freebuild, rpserver and more

Does it happen every time?:
yes