The bug of not unlocking the achievements existed because the UI element told you it was completed, but the internal data the achievement was using was not on the same page. The UI code and scenario results code have been changed, now it should be impossible for all of the scenarios to show up as completed while the achievement is not unlocked. As expected, this can result in scenarios suddenly not showing up as completed anymore. Sorry about that 🙂
The fact that you saw this happen with the same scenario is very useful information, thank you for the feedback!