It's always tricky when manga authors plan the endings of their works. In 2001, Hiroaki Samura noticed that Blade of the Immortal, which he was planning to end at 5 volumes, had exceeded 12. So, he observed "I want to finish it within the next 3 years." The series has still yet to wrap up after 28 volumes. With that in mind, Kenjirou Hata is now saying that, with the 30th volume, Hayate the Combat Butler is 60% complete.
Hata tweeted this on the occasion of the manga series going on hiatus until mid-February. The author attributed the break to other commitments and downplayed health concerns.