It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) was asked on the day of 10th Dhul-Hijjah about a person who gets his head shaved before offering the sacrifice, or if there is any other change in the prescribed order, then what is the ruling? The Prophet (peace and blessings be upon him) kept replying to every question, "There is no harm."
Hadith Referenceمسند احمد / ومن مسند بني هاشم / 2731
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد حسن