Comment by Electricniko

For some reason the Kennedy Center one is saying not available right now, but this was the link for it if it returns:

https://www.youtube.com/watch?v=NaJklsJonD4

The main broadcast is still up, with the ten minute countdown starting around 5 hours and 27 minutes into it:

https://www.youtube.com/watch?v=Tf_UjBMIzNo