It is also permissible for a pilgrim to grow their hair for a month as a concession. This was narrated by Hisham ibn al-Hakam and Isma‘il ibn Jabir from Imam Jafar ibn Muhammad Al-Sadiq عليه السلام, and also by Ishaq ibn Ammar from Abu al-Hasan Imam Musa ibn Jafar Al-Kadhim عليه السلام.