What is the ruling on the preacher abandoning standing on the minbar for the Friday sermon if it is available?

Standing during the sermon is obligatory because it was a continuous practice of the Prophet, peace and blessings be upon him, unless there is an excuse such as illness or inability to stand. As for requiring a minbar to stand on during the sermon, it is not obligatory, as the Prophet, peace and blessings be upon him, used to deliver sermons while standing on a tree trunk. However, it is advisable to counsel the Imam that it is preferable to stand on the minbar due to its benefits and in following the Sunnah of the Prophet, peace and blessings be upon him.