If a man performed the Fajr prayer in a state of Tayammum because there was no water, would he then have to repeat his prayer if he [later] found water after the sun had risen?
Category: Salih al-Fawzan
https://www.alfawzan.af.org.sa/
Preparation for Ramadhan
There are things that are impermissible for the one fasting [to do] even though they do not nullify his fast. They are called “Mufattiraat Ma’nawiyyah” (figurative nullifiers).