If you are planning a trip in October, buying SSR resale will take about 6 weeks or so, bringing you to July before you can book. There might still be availability at SSR or OKW (I think BLT would be a lot harder to get) but October is a popular time for
DVC (food and wine) so you never know.
BLT does have lower MF's, but the initial buy in is quite a bit more than SSR. If you really are okay not always staying at BLT, then going that route will cost you more upfront (and no one knows for sure that the MF's will always be the lowest--SSR's are pretty low as well).
I only wanted BLT and bought there, even though I knew it cost me more money. But I would not have been happy anywhere else, can always book 11 months in advance, and wanted to know for sure I had a room there so the extra money was worth it for me.
If you think you would be happy being at SSR, at least when you could not trade out, then that is really the best value right now.
Of course, going with BLT, direct from Disney, will give you points immediately and you could make a reservation within days so your chances of getting an October room somewhere will be greater than going SSR resale.
Give a DVC guide a call and tell him/her that you are considering BLT but not sure whether you would be able to use it in October--they can at least tell you what availability looks like right now. While availability changes daily, at least you would have a true answer of whether or not you have a shot at a room.
Good luck!