Is blood that continues for two consecutive months and appears as menstruation at some times of the day and as istihadah at other times to be considered a continuation of the previous menses or istihadah?

The minimum period of purity between two menstrual cycles is 13 days according to the Hanbalis and 15 days according to the majority of scholars. The cessation of blood for a week does not remove the description of istihada (prolonged vaginal bleeding outside of menstruation). If the woman has a previous regular cycle, she should refer to it. Otherwise, she should rely on valid differentiation (between menstrual and non-menstrual blood). If she has neither a regular cycle nor valid differentiation, she should consider 6 or 7 days of the month as menstruation, based on her best judgment, and anything beyond that as istihada. She should continue this practice until Allah shows her purity for a period equal to the minimum purity period between two menstrual cycles.