Narrated from Abdullah bin Amr bin Al-As (may Allah be pleased with them), he said: "The Messenger of Allah (ﷺ) was standing for the people at Mina during the Farewell Pilgrimage, and people were asking him questions. A man came and said: O Messenger of Allah (ﷺ)! I did not know and I shaved my head before sacrificing, so the Prophet (ﷺ) said: 'Now offer the sacrifice, there is no harm.' Another man came and said: O Messenger of Allah (ﷺ)! I sacrificed before stoning the Jamarat and I did not realize, so the Prophet (ﷺ) said: 'Now stone (the Jamarat), there is no harm.' Abdullah bin Amr bin Al-As said: Whatever matter was asked of the Messenger of Allah (ﷺ) regarding doing something before or after its due time, he (ﷺ) said: 'Now do it, there is no harm.'"
Hadith Referenceمسند الإمام الشافعي / كتاب الحج / 1018
Hadith Takhrijأخرجه البخاري، الحج، باب الفتيا على الدابة عند الجمرة (1736) ومسلم، الحج، باب جواز تقديم الذبح على الرمي والحلق على الذبح .... الخ (1306)۔