For those that haven't been members for decades, honestly we don't know for sure how it works any longer. We know how it used to work (the five days out MANY years ago stuff), but things have changed.
When we bought in 2001 they claimed rooms were assigned on a first book, first request made system. This was before BCV opened, and when Boardwalk View was not yet a booking category. And it was Boardwalk View that drove that. They made BW view a booking category, opened up SEVERAL more resorts, and sometime in there announced they were moving to "room ready" - they gave you a room that was available when you arrived - they never said they wouldn't try to meet requests, but apparently that was no longer the priority. That, of course, throws a wrench in any "early bookers get their requests met" since the requested "high floors" might all be clean and ready to hand out to the early arrivers, and you, who booked right at eleven months but aren't arriving until 4pm, end up not getting your requests met.
I'm not sure if they've told us what they are doing now - or if there are even human room assigners any longer (I doubt that system exists in the scale and scope of many years ago). It does seem to vary by resort, with some resorts being a little better at meeting requests than others. You can't prioritize both "room ready" and "requests met in order placed" - at least without sacrificing a lot of efficiency in housekeeping.
If I ran the zoo, I'd go back to the requests filled as close as possible in the order they were made system - by humans if it isn't done so. And I'd tell anyone who wanted a different room that "it isn't possible - all the rooms have been assigned in the order you booked - and if you didn't get what you wanted it wasn't available when your room was assigned" and yes, you have to wait until after 4 to get into your room sometimes, and sometimes - especially if you book last minute - you end up with a crappy view. BUT, I'd make one of the requests "room available early" - and I'd clean the less desired rooms first - the ones no one requests. Those requests everyone makes, those are the ones that are prioritized for cleaning last. Because in this sort of system, everyone needs to make a few sacrifices for it to work - everyone can not have the room they requested, available when they check in at 10am.