Why cannot we do two adventure island on the weekinds as it was at the start of the game, when we still have two rotations of islands?

Hello, I was wondering are the adventure islands on the weekend maybe bugged? When the game started we were able to do 2 per day, but now we are not able to anymore even tho the adventure islands still have the two rotations aka 3 different islands from 11 to 15 and then it changes from 19 to 23 to 3 different ones again. Thanks in advance for the explanation.

And why are the adventure island times from monday-friday so messed up? Why is there no slot later than 23h? For a workong person coming home later than 23h its literally impossible to do adventure island on the weekdays.