Answer

Rāīsi Pratikraman should be started after sunrise, in the morning.

Traditionally, it is performed after the night has ended and the new day has begun, as it is the morning Pratikraman for reflecting on faults committed during the night.

Explanation

In Jain practice:

• Rāīsi Pratikraman is done in the morning.
• It is connected with repentance for mistakes, carelessness, or violence that may have happened during the night.
• It should not be done before sunrise as a general rule.

If you follow a specific Gacch, Sampradāy, Upāśray, or Guru tradition, it is best to follow the timing instructed there.

Takeaway

Start Rāīsi Pratikraman after sunrise, with calmness, devotion, and awareness.