How is menstruation determined when the bleeding starts black for the duration of the habit (five days) and then turns red and continuous?

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If, instead of black blood, she sees red blood which then turns black and exceeds the usual duration, the ruling for the black blood is nullified due to exceeding the maximum duration of menses, and the red blood is considered her menses because it corresponds to the time of her habit. If she sees red blood during the time of her habit, followed by five days of black blood, which then turns red and continuous, those prioritizing habit rule that her menses is the days of her established habit. When the black blood recurs, the Qadi rules it becomes menses. Those prioritizing differentiation rule that the black blood alone constitutes the menses.