the Prophet granted the camel herders a concession allowing them to stone the Jamrat on one day an not another.
Sunan an-Nasa'i Book 24, Hadith 451
← Previous Hadith "The Mesenger of Allah was asked questions during the days of Mina and he said: 'There is no harm.' A man said: 'I shaved my head before offering the sacrifice.' He said: 'There is no harm.' Another man said: 'I stoned (the Majarat) after evening came.' He said: "There is no harm.'"

Sunan an-Nasa'i Book 24, Hadith 450 Next Hadith → the Messenger of Allah granted a concession to some camel herders, allowing them to not stay overnight in Mina, and allowing them to stone the Jimar on the Day of Sacrifice, then to combine the stoning of two days after sacrifice, so that they could do it on one of the two days.

Sunan an-Nasa'i Book 24, Hadith 452