I get the impression that they’ve made a conscious decision to only sell to membership holders come what may. Whether this changes for cup matches when there are a lot more tickets to shift we’ll have to wait and see.They want the membership on top though, as most of these tickets will give very little markup to the club if the season ticket holder sells them. Less than £4 or in some cases a loss of £15 if an adult resells as a child (big bonus if other way around I know).
There are different sales tactics each year, I expect it to change when they have exhuasted membership sales.