The Messenger of Allah ﷺ announced our departure during the year of the Conquest after two nights of Ramadan had passed. We set out fasting until we reached al-Kadid, where the Messenger of Allah ﷺ ordered us to break our fast. The next morning, some of the people were fasting and others were not, until we reached the nearest stopping place where we would meet the enemy. He then ordered us to break our fast, and we all did so.
أذنا رسول الله ﷺ بالرحيل عام الفتح في ليلتين خلتا من رمضان، فخرجنا صواما حتى إذا بلغنا الكديد فأمرنا رسول الله ﷺ بالفطر، فأصبح الناس منهم الصائم، ومنهم المفطر حتى إذا بلغ أدنى منزل نلقى العدو أمرنا بالفطر فأفطرنا أجمعين.
Ahmad (11825) narrated it from Abu Mughira, who said, Saeed bin Abdul-Aziz narrated to us, he said, Atiya bin Qays narrated to me, from someone who narrated to him from Abu Saeed, and he mentioned it. Its chain is sahih, and the unnamed narrator is Qazaa bin Yahya. Bayhaqi related it in Dalail (5/24) through another route from Saeed bin Abdul-Aziz Tanukhi, from Atiya bin Qays, from Qazaa bin Yahya, from Abu Saeed, and he mentioned the same.The hadith of Abu Saeed specifies that the Prophet ﷺ set out from Madinah on the second of Ramadan, while Zuhri specifies that the conquest took place on the thirteenth of Ramadan, which implies that their journey between Madinah and Makkah took eleven nights.