So here's a good question. Last season the jury was only 7 people and they called it to commemorate 25 seasons the jury was going "old school" and only have 7 members like they did between seasons 4-14. It wasn't until season 15 that it was expanded to 9. So this year will they go back to the 9 they adopted in season 15 or keep it at 7 like last season.
Last year, they didn't announce the smaller jury until week 7 and I guarantee you production is aware of this should they want to make a change and manipulate it. The BB26 wikipedia page states its 9 people but has no source to confirm that and we know wikipedia is open to anyone to edit and cannot be reliable without sources being sited.