Any way to coin this name?

Pretty much, I've had my display name as Spring, and my handle as @ SubToSpring. Obviously, when you use the address link it brings up my channel. However if you do the address link for the channel with the handle "Spring," it gives you the 404 NOT FOUND message. I've used a couple Youtube name availability checkers, and they all say the name is free. Plus, I've scrolled through dozens of pages just searching the channel name @ Spring and setting the filter to channels and there were none, but when I try to change my handle to Spring, it says it's not available. Am I doing something wrong, or is there a glitch?