I was allowed to split my first purchase of 200 pts. at BLT into 2 - 100 pt contracts. I think I read somewhere that one (the first) contract has to be at least 100 pts and the second can then be 60 pts., but the total purchase has to be equal to or greater than the minimum purchase for the resort.
When I did this my guide told me that it wasn't possible initially, but I knew better from reading DIS. So I pressed her on it and she said she would ask "MGMT". When I continued to ask, it was allowed. I know a few others on DIS have reported this same scenario. So, I wouldn't take no for an answer, if that's what you want to do. It seems when it becomes a deal breaker for making the purchase,
DVC allows it.