Have you bothered reading the statement?
"It was always the Club’s intention to release new Season Tickets as part of the expansion of the North Stand. Whilst the seating configuration of the stand is yet to be finalised, we can confirm that it will be predominantly GA seating and that the majority of the additional GA seating capacity will be held by Season Ticket Members, through the release of new Season Tickets."
There's around 8,000 new seats, a majority means 4,000 plus. There's also 500+ new ones for next season. Note that this doesn't mean just the new stand, but means the entire stadium.
"We will also commit to offering Cityzens Matchday and Junior Members the opportunity to purchase Season Tickets which become available from non-renewals in future seasons."
The above is promising as well.