As far as I recall, NHK's never mentioned their KU feed on their website, only their C-band feed. The "important notice" that page links to says the following:
"The viewers who are watching NHK WORLD TV, receiving the channel’s signal from a satellite using a large-size antenna (over 1 meter in diameter), are kindly requested to check your satellite receiver and confirm whether your equipment can continue to receive NHK WORLD TV’s new signal after July."
I don't think this will affect their Ku feed, but we'll just have to wait and see.