I think what they've done is subtracted the remaining tickets from the total allocation (which is 5,850).
But that many were never on sale. In fact, I think it only started with something like 3k tickets as not all blocks were open for sale at that point.
The club would have separated the qualifying sales criteria based on the number of people in each bracket. So we'll be looking at something more like 250-350 sold with each new bracket.
There were 10 brackets listed, which is about 3,500 fans. Given the club has probably given 850 tickets to players, corporates, sponsors etc that says to me there could be another 1.5k ticket left available at 5 pm tomorrow - or if we're being very pessimistic with numbers, let's say 500 tickets left.
The more I think about it, the more I reckon everyone will get one who qualifies tomorrow.