Well that is great. I am assuming you will be there for 3 years in the 14 month timeframe.
I have not even purchased yet (I plan on purchasing at BCV), But I think I can answer most of your questions and I am sure someone will correct me if I am wrong.
VWL is estimated to be sold out be the end of this year or sooner. There is some pretty good rumors that BCV will pre-sell (meaning that they won't even be open yet). My guide told me he suspects it would be before March 2002 for the pre-sell.
If you book at your home resort you can book 11 months in advance, if you book at a sister (another DVC) resort you can book up to 7 months in advance. Each DVC resort has its own
point chart, it does not matter if it is your home resort or a sister resort. But I beleive each new resort has been a few points more than the previous resort in general per night. (Someone please verify this). Meaning that OKW is the least amount of points per night in general, then BWV, then VWL.
As far as an add on goes. Say you buy 100 points at VWL and then 100 at BCV. You could book up to 100 points worth of night 11 months in advance at VWL and then 100 points worth of nights 11 months in advance at BCV. If you wanted to use all 200 points to stay at one place, you could book 100 pts each at the 11 month at both resorts (lets just say 6 nights at VWL and then 6 nights afterwards at BCV) then at the 7 month time frame you could try and switch to the first resort for the last 6 nights.
I hope all this helps and I am sure if I am incorrect on anything someone will help.