How do I change the monster week when transitioning from day 7 to day 1?

I don't know... I've had similar cases too... In Heroes 3, which was similar to 3.5, the menu often displayed errors (for example, "Create Maps" or "Save Game"). The week names were also strange: "Week of Drowning" or something like that... I had some strange heroes... Not 3.5, but still more than 3...