Nope! She'll be on at some point between 6 and 8am Saturday morning in the UK so technically it's kinda early for us, it's actually worse for New Yorkers than us this time since they'll have to be on at 3am to watch her live! The concert *apparently* ends at 9am-ish UK time and she's second to last on, that's where I'm getting my 7am estimate from. Set your alarm tomorrow morning at your own risk, I dunno for sure if she is on at that time.
I think I'm going to get up at 6am, check a couple forums to see what's happening and then go back to bed if I've missed her/she wont be on for another couple hours.
I'll do a bit more looking around and edit this post or post again if I find anything concrete. KPDaily is my source for the 9am GMT end to the show though.
Edit: Yup, ends 9am GMT. Here's a Live Stream link which gives that end time:http://music.yahoo.com/programs/iheart/