No, I don't think it works that way. Now I don't know quite how it works

but I can tell you we've had one BRs on the 4th and 5th floors. Word is BCV is normally close to sold out. I always wondered if that was hype when I read it on the DVC boards but Teena has said so, too.
It may be that a certain percentage are held as 2 BRs or that it is first reserved, first fulfilled. Or some other formula?
But if you are asking for 4th or 5th floor for a better view of Illuminations, I truly don't think it matters that much. We've been on every floor except the first on that side. We've always seen the high effects and have never seen the lower. I would just request Epcot side and try not to worry about the floor.