We submitted our 10th submission just before the announced deadline of Dec 22nd and at that time the website showed that the deadline is Dec 22nd.
Now, when I look at the website, I see the deadline was extended to Dec23rd. We didn't know about this extension and we would surely use the extra day if we knew it on time.
The challenge was not extended. I believe that Ben who manages the site may have had to temporarily re-open it for a group who's submissions had failed yesterday due to a problem on the website. I think it had to do with their submitting from a Macintosh computer and the site rejected it because of how the Mac handles .zip files. So the group is being allowed to resubmit their previously attempted results.
Thanks again for your participation in the challenge,
I see ...