Ruling 470

If a woman with a habit of time – irrespective of whether she also has a habit of duration or not – experiences bleeding during the time of her habit, or on one or more days earlier than the time of her habit such that it can be said that her habit has moved forward, then even if the bleeding does not have the attributes of ḥayḍ, she must act according to the rules that were mentioned for a ḥāʾiḍ. In the event that afterwards, she realises that it was not ḥayḍ – for example, her bleeding stops in less than three days – she must make up the ritual acts of worship that she did not perform [when she considered her bleeding to be ḥayḍ].