I thought a few months ago the general speculation (with US buyers, since our little Canadian queue hadn't started yet) was that Tesla was essentially pre-building in batches, then matching built cars to owner orders. Assuming that's true, I can easily see that some later orders just happen to match up with cars that were built in a particular batch (e.g., red paint) and therefore the "later" [EDIT: owners] orderers get served first.
I haven't pulled in all the details of this thread and who posted to try to figure out if there are cases that prove the above is not what is happening (and... I won't be...), but that seems plausible to me how Tesla can get the most cars to the most customers in the shortest time, given their current ramp. There will be some outliers who are left out in the cold as it were, given the luck of the draw. I do believe the "previous owner" advantage applied to reservations and initial ordering, NOT build and delivery.
Anyway, just a theory, in case it helps. I know how frustrating it is to now be so close...but so far... I purchased an inventory car and had to wait *3* *whole* *days* to pick it up, and that drove me nuts and couldn't sleep. The lack of knowing exactly when, like what some of you people are going through, would make it even worse.