Is the onset of menstrual bleeding at the very end of the Asr time considered the first day of the cycle, or does the count begin from the following day? And if menstruation exceeds 15 days, is the day on which bleeding occurred just before the Asr adhan included in the duration of menstruation to determine istihadah, or does the count begin from the following day?

If a woman sees blood after 'Asr, the fifteen-day period completes at the corresponding time, meaning after 'Asr on the fifteenth day, and during this period the blood is considered menstruation. However, if the bleeding exceeds this period, the woman is considered to be experiencing irregular bleeding (istihada). The fifteen days are not counted from the day after seeing the blood, but rather from the time the blood is seen until the corresponding time after fifteen days.