When I visited I think they said the 15th. That being said I think they keep it intentionally vague on the website because, based on old threads on GC, they have had some issues with meeting specific deadlines for results.
I don't know about funding - would be interested in any insights people have. I have noticed that on GC some people were able to use higher funding offers from other schools to renegotiate with Harris, although the increases were generally pretty small.