By Allah, I know best among the people the proper time for this prayer, the late evening prayer. The Messenger of Allah ﷺ used to pray it when the moon set on the third night of the month.
أخبرنا عثمان بن عبد الله قال حدثنا عفان قال حدثنا أبو عوانة عن أبي بشر عن بشير بن ثابت عن حبيب بن سالم
والله إني لأعلم الناس بوقت هذه الصلاة صلاة العشاء الآخرة كان رسول الله ﷺ يصليها لسقوط القمر لثالثة
[Its isnad is sahih] Abu Dawud transmitted it in the Book of Prayer, Chapter on the Time of the Late Evening Prayer, no. 419, and Tirmidhi in the Book of Prayer, Chapter on What Has Been Said Regarding the Time of the Late Evening Prayer, nos. 165 and 166, from the hadith of Abu Awana with this same chain. Abu Bakr bin Arabi and Nawawi both graded it sahih.