You can't change your handle, so this April Fool isn't down to the club. Someone's been at the Photoshop.
I'm well aware it's not serious. I was just wondering whether someone had made a daft spoof or if the official one had changed theirs as a joke. Tuckin's post above seems to answer that.
Ah, apologies - it seems you can change it, although this brings complications: "The problem is this opens some strange loopholes in the Twitterverse. Your new tweets will come from @NewName. Your old ones will stay on your profile, rebranded with @NewName. But any tweet or retweet you were mentioned in will still be under your @OldName, and will no longer be linked to your account. Conversations will suddenly become very one-sided, as all the messages from the second party disappear, leaving only your own. This is because mentions in tweets are based on text, not unique IDs, so Twitter will not change your friend’s tweet just because you changed your name. Instead, the link will go to a 404 page… that is, until someone snaps up your old handle."