That's the plan because if there were plenty of tickets available on the day a lot of people wouldn't bother with season tickets.
Adult season ticket: £30/match
Adult matchday ticket: £35-49/match
Seems to me that you'd like to increase the amount of single matchday ticket purchases.
It's reasonably sensible to create that demand and guarantee season ticket sales with a lower capacity. And obviously those last 3-10k seats would be the most expensive to build. I'm just curious on their calculations and what the breakdown will be. Feels to me that with a 52k capacity we'll:
1) Be disappointing a few people on the waiting list if uptake is high
and more importantly, 2) reach a bottleneck where there aren't actually enough tickets available for later generations of young fans to actually become season ticket holders