Praise be to Allah.
If a woman enters ihram for ‘Umrah, then her period comes and she does not become pure from it before ‘Arafah, then she should intend to do Hajj, and thus it will become Qiraan, as happened to ‘Aa’ishah (may Allah be pleased with her). She was doing Hajj Tamattu‘, then her menses came after she entered ihram for ‘Umrah, and she was not able to do ‘Umrah before Hajj. So she joined Hajj to ‘Umrah, and it became Qiraan.
Narrated by al-Bukhaari (305) and Muslim (1211).
It says in Zaad al-Mustaqni‘: If a woman menstruates and she is afraid that she will miss Hajj, she should enter ihram for Hajj, and it becomes Qiraan.
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said: What is meant by woman here is the woman who is doing Hajj tamattu‘, i.e., she entered ihram for ‘Umrah so that she could then exit ihram, and perform Hajj in the same year, and she reached Makkah on the fifth day of Dhu’l-Hijjah and got her menses, and her period usually lasts six days, so she will become pure (taahir) on the eleventh, i.e., after the standing [in ‘Arafah] is over; hence she cannot do tawaaf and saa‘i and end her ‘Umrah.
We say to this woman: You have to enter ihram for Hajj, so that you will be doing Qiraan, because the Prophet (blessings and peace of Allah be upon him) instructed ‘Aa’ishah to do that when her menses came in Sarif before she entered Makkah. The basic principle with regard to a command or instruction [of a text] is that it implies something is obligatory.
End quote from al-Sharh al-Mumti‘, 7/98
Sarif is a place near Makkah.
Thus it is clear that this woman will not be able to do Hajj tamattu‘; rather she should change it from tamattu‘ to qiraan, and she has to offer a hadiy just like one who does tamattu‘.
And Allah knows best.