Do the rulings on habitual doubt continue to apply after menstruation, and is doubt considered habitual on the day following its first occurrence?

The "mustankah" is someone who is overwhelmed by doubt and experiences it frequently on a daily basis. The Malikis have stipulated that whoever experiences frequent doubt is excused, and the mustankah must ignore the doubt and not pursue it, because it corrupts the religion. However, if the doubt occurs for the first time, or happens at widely spaced intervals, its owner is not considered a mustankah.