Sayyiduna Abu al-Darda (may Allah be pleased with him) delivered a sermon saying that whoever is overtaken by the morning has no witr. This was mentioned to Sayyidah Aishah (may Allah be pleased with her), and she said: Sayyiduna Abu al-Darda has erred, for the Prophet (peace and blessings be upon him) would reach the morning and then pray witr.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4518