Funny story, turns out I forgot to commit our latest date_parser before Thanksgiving break and then accidentally over-wrote it with the one from the repository because I thought it would be the most up to date.

So, the current date parser has some bugs that were caught and fixed and then lost. The good news is I have re-fixed most of all those bugs and I just tested "11th Dec to 13th Dec" and it parsed it correctly. The new parser should be pushed live in a day or so.