UFA won't let 'Hello! Morning' be canceled. Period.
Looks like I spoke too soon. In introducing today's HaroMoni Academy, Yuko said ??????????????????.
Translation: "We would like to do the graduation ceremony of HaroMoni."
Well damn.
EDIT: What the hey? I can't input original Japanese here? Okay, screenshot instead...

Of course, I could be grossly misunderstanding this. Yuko's discussion leading up to the announcement consisted of "March is the season for graduations, blah blah blah." Perhaps when she says "HaroMoni", she means "the cast of" and not the show itself. That would jive with the premise of this week's Academy: overcoming, or "graduating from", their weak points. I'm not sure yet...
I really hope it's not the end of the show, but between this and the scheduled clips shows, I can now see how the rumor got started. We'll know soon enough.