Sometimes I pray Witr while listening to the mu'adhdhin call the Fajr adhan. Is the Witr in this case considered valid?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: I delay the Witr until the end of the night and go to sleep, and I may not wake up until shortly before Fajr. Sometimes, while I am praying the Witr, I hear the mu'adhdhin calling the Fajr adhan. Is the Witr in this case considered valid, or is it outside its time?

Answer:
If you have entered the rak'ah, and then the adhan is called while you are standing, you complete the rak'ah and it is valid, if Allah wills, because you caught the last time for the Witr before the dawn appeared. Yes.