Ruling 628:
Salat al‑wahshah can be performed at any time on the first night of burial. However, it is better to perform it at the start of the evening after ʿishāʾ prayers.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)
Purity: Timing of Salat al‑Wahshah
Practical Laws of Islam as per the teachings of Ayatullah Sistani
