Imam Hussain Youtube Channel has documented the ceremony of replacing the black banner of the dome of the Imam Hussain Shrine with a red one on the first of Rabi’ AlAwal 1440 A.H.
Click the link below to watch a video:
https://www.youtube.com/watch?time_continue=60&v=FiMafnpYki4
Source: imamhussain.org