Answered by Shaykh Faraz Rabbani
Is it Sunnah to change one’s spot to another after paying the fard prayer?
It is recommended to do so, especially for the imam. (Shurunbulali, Maraqi al-Falah) The wisdom behind this is: (1) so that someone who comes to the mosque or place of prayer late doesn’t think that the congregational prayer is still in progress; and (2) to have more of the earth bear witness for one on the Day of Judgment.
And Allah alone gives success.