al-Hakam bin 'Utayba الحكم بن عتيبة · The Book on Zakat

the Messenger of Allah sent a man from Banu Makhzun to collect charity, so he said to Abu Rafi: "Accompany me so that perhaps you may have some of it." So he said: "Not until I ask the Messenger of Allah." So he went to the Prophet to ask him, and he said: "Charity is not lawful for us, and to be the Mawda of a people to be the same as them."

"Al-Abbas asked the Messenger of Allah about paying his charity (Zakat) in advance before its time is due (by being in possession for a whole year), he permitted him to do that."