بسم الله الرحمن الرحيم
(Fatwa: 431/351/D=04/1435)
It is makrooh to perform salah 20-25 minutes before sunset when the sunlight gets yellow to an extent that one can stare at it, but if someone performed it will be valid in spite of being makrooh. It is severely makrooh to delay salah to sunset time and it is worse to make it a habit.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband
