Since the only thing I've never known NP to delay timing on is a YouTube or radio interview, either some more news is on the horizon that he would like to share, or it's possible something just came up more important (ie Family matter, big meeting that can't be moved etc).

All speculation of course. I guess someone could always email and ask if they wanted. I personally don't plan to in the event its a private matter. Hopefully all is well and this is for a good reason mentioned by others.