Story cliffhanger??

Absolutely a rejection. Finish the story. You can imply that there are further adventures, but this adventure must conclude.

And only imply the further adventures, don't start into them. "We set off over the hill, wondering who would hunt us tomorrow" is good. "We set off over the hill, then dodged as the dragon breathed fire" MIGHT work. Just a line or two that implies that they're going to have to keep their eyes open might work (like in the ending to Catch-22). But they fight the dragon, one of them is injured, they have to go find a healer, and THE END is going to get rejected.

There are markets for ambiguity. This isn't one of them.

A particular problem I hear from the slush team is "Here's the first 16,999 words of my novel! It ends on a cliffhanger." They tell me that if a story is close to the limit, they check the ending first to make sure it is an ending. It saves them time.

Thank you. That's kind of what I thought.

I appreciate your insight into the workings of the contest.

My WotF semi-finalist was a bit of a cliffhanger, and the editor told me to finish the rest of the story.

The MC's heart's desire did get resolved, but I left it too open at the end. A bigger, world impacting, heart's desire sprang up at the end to lead into next part.

I viewed the story as part 1 of 3 smaller stories that combined would complete a larger tale. I guess I just didn't wrap up part 1 enough.  When I started part 2 I also realized that to make it stand on its own I had to do all the introductions of characters again. That would have bogged down and killed part 2. So, now I have a plan to take what I started in part 2 and add it to the end of part one to continue on. Can't turn it into WotF again, since it is a SF, but I learned something from the editor. That knowledge, for what it's worth, is now passed onto you.

State your MC's heart's desire, fight for that throughout the story, and resolve it in the end. Give a nice wrap up, with sugar sprinkles on top if you have some, and call the story done.  You can then write a new story with same MC and another heart's desire later, but don't cliffhang the first one. A small hillhang is fine, but stay away from the cliff...  

Thank you for the advice...

Yeah, I have this very neat story idea but dagnabit, the way it needs to come in just under 17,000 words, I needed it to end on a cliffhanger, but I guess I will work on it as a novella or something to that effect.