The challenge I see here is around parsing,
“11th Feb” vs
“11/2” vs
“2/11” (cause USA) vs
“11-02” vs
“Feb 11” vs
“Feb 11, 2017” vs
“Feb 2 - Come to the maker fair”
“Come to the maker fair - Feb 2”
It is a solvable problem but there is a lot of magic that would need to be added.
I think the first step here would be to build a plugin for it.
I am not that concerned about abuse cause you could simply ban abusers from posting in the category that allows for this magic behavior if you wanted to.