Sounds like a bit too convoluted, IMO, since there is no real shame or trouble just scrapping a month that does poorly. It's not like it's unique either. People already did it, so they might feel uninspired or less inclined to make time for it, or other reasons get in the way, but why extend it just because it's not popular? If the forum was working as usual, would we be considering extending the month and deregulating the normal voting pattern?
Not every month can have 18 stories and everyone on the edge of their seats I guess.