Q. Can a person perform Nafl Salaah between the Azaan of Fajr and the Salaah of Fajr, between dawn and the Salaah of Fajr?
A. After the break of true dawn (Subah Saadiq), it is not permitted for one to perform any optional (Nafl) Salaah with the exception of performing the two Rakaats Sunnah of Fajr Salaah and any outstanding (Qadha) Salaahs before performing the Fardh of Fajr Salaah.
As for performing Salaah after having performed the Fardh of Fajr Salaah, one is only permitted to perform Qadha Salaahs. The performance of any Sunnah or Nafl Salaahs are not permitted during this time until after sunrise. (Fataawa Darul Uloom Deoband 1/59)
Note: One should not perform Qadha Salaahs in public; rather, it should be performed at a time and a place when there are no observers around to avoid any form of suspicion against oneself.
Allah Ta’ala Knows Best
Mufti Ismaeel Bassa
This answer was collected from TheMufti.com, which is a fatwa portal managed by Mufti Ismaeel Bassa from South Africa.