She obtained a khul divorce during the time of the Prophet ﷺ, and the Prophet ﷺ instructed her, or she was instructed, to observe a waiting period of one menstrual cycle.
حدثنا محمود بن غيلان أنبأنا الفضل بن موسى عن سفيان أنبأنا محمد بن عبد الرحمن وهو مولى آل طلحة عن سليمان بن يسار
أنها اختلعت على عهد النبي ﷺ فأمرها النبي ﷺ أو أمرت أن تعتد بحيضة
[Its isnad is hasan.]Ibn Majah narrated it in the book on divorce, chapter on the waiting period of the woman divorced through khula, no. 2058, and Nasai narrated it, 6/186–187, no. 3528, both from the hadith of Rubay bint Muawwidh with the same wording.There is also a report on this subject from Ibn Abbas [which follows next, in the same chapter, no. 1185b].