"Chelsy" song??

I've been hearing a song on the radio at work by someone called "Steffi" (don't know exact spelling), which has the word "Chelsy" (spelling again! Presumably not the same as the footie team!) in it a lot. It's a great song. Anyone know when it's released as I can't find anything about it online even though I've tried variations on the spelling. Thanks for any help!