The Prophet (ﷺ) said, "Whoever slaughtered (his sacrifice) before the `Id prayer, should slaughter again." A man stood up and said, "This is the day on which one has desire for meat," and he mentioned something about his neighbors. It seemed that the Prophet (ﷺ) I believed him. Then the same man added, "I have a young she-goat which is dearer to me than the meat of two sheep." The Prophet (ﷺ) permitted him to slaughter it as a sacrifice. I do not know whether that permission was valid only for him or for others as well.
Sahih al-Bukhari Book 13, Hadith 6
← Previous Hadith Allah's Messenger (ﷺ) never proceeded (for the prayer) on the Day of `Id-ul-Fitr unless he had eaten some dates. Anas also narrated: The Prophet (ﷺ) used to eat odd number of dates.

Sahih al-Bukhari Book 13, Hadith 5 Next Hadith → The Prophet (ﷺ) delivered the Khutba after offering the prayer on the Day of Nahr and said, "Whoever offers the prayer like us and slaughters like us then his Nusuk (sacrifice) will be accepted by Allah. And whoever slaughters his sacrifice before the `Id prayer then he has not done the sacrifice." Abi Burda bin Niyar, the uncle of Al-Bara' said, "O Allah's Messenger (ﷺ)! I have slaughtered my sheep before the `Id prayer and I thought today as a day of eating and drinking (not alcoholic drinks), and I liked that my sheep should be the first to be slaughtered in my house. So slaughtered my sheep and took my food before coming for the prayer." The Prophet (ﷺ) said, "The sheep which you have slaughtered is just mutton (not a Nusuk)." He (Abu Burda) said, "O Allah's Messenger (ﷺ)! I have a young she-goat which is dearer to me than two sheep. Will that be sufficient as a Nusuk on my behalf? "The Prophet (p.b.u.h) said, "Yes, it will be sufficient for you but it will not be sufficient (as a Nusuk) for anyone else after you."

Sahih al-Bukhari Book 13, Hadith 7