The reply is:
Yes. However, in the language of the early generations, the term “waiting period” applies both to the three cycles and to establishing that the womb is clear by waiting for one menstrual period, as illustrated by the examples already given. Thus, if ʿUmar and ʿAlī held that a woman separated by khulʿ and others in similar circumstances must wait for one menstrual period, then that is what they meant here. If, however, they held that she must wait for three cycles, then the Companions held two views on this matter, for it is established that ʿUthmān held that a woman separated by khulʿ must wait for one menstrual period.

If it is said:
“We may instead hold that a woman separated by khulʿ must wait for one menstrual period, whereas a woman in an invalid marriage must wait for three cycles.”

Then anyone adopting this position must explain the distinction between the two cases.

If it is objected:
“ʿUmar and ʿAlī differed over whether she becomes lawful for the second man to marry. ʿUmar said, ‘He may never marry her,’ whereas ʿAlī said, ‘Once her waiting period has ended—meaning the waiting period arising from the second man—she may marry if she wishes, or refrain from marrying if she wishes.’ If intercourse with the second man were like intercourse under a mistaken belief of lawfulness, it would not prevent the first man from marrying her. For if a man’s wife has intercourse under a mistaken belief of lawfulness, his marriage does not thereby end, by scholarly consensus. Rather, he must refrain from intercourse with her until she completes her waiting period. Likewise, if a revocably divorced woman has intercourse under a mistaken belief of lawfulness, nothing extinguishes her husband’s right?”

The reply is:
First, this objection has no bearing on the length of the waiting period. Whether it consists of establishing that the womb is clear by waiting for one menstrual period or of waiting for three cycles, the objection arises in either case.

There is no doubt that if the husband who divorced her, and on account of whose intercourse she observes a waiting period, has divorced her for the third time, she has become unlawful for him until she marries another husband. He therefore cannot take her back during her waiting period following divorce from him. But if he has separated from her irrevocably, as in khulʿ, and she marries during her waiting period following separation from him—for example, before her womb has been established to be clear by one menstrual period—then, if he wishes to marry her during her waiting period, he may do so only under a marriage contract