Purity: Prayer if Ḥayḍ Stops at End of Time
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 462:
If at the end of the time for prayers a woman’s ḥayḍ stops and she has time equivalent to performing ghusl and one rakʿah or more of the prayer, she must perform that prayer; if she does not, she must make it up.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)