Is it permissible to make up the post-Dhuhr regular sunnah prayers after the Asr prayer upon returning home, and how should one deal with the pre-Dhuhr regular sunnah prayers, knowing that the Dhuhr prayer time at the university is fixed between classes?

It is legislated to make up for missed regular supererogatory prayers (Sunan Ratibah) if they were missed due to a legitimate excuse, such as sleep, forgetfulness, or preoccupation. It is permissible to make them up during times when prayer is generally prohibited, according to the majority of scholars, who cite the actions of the Prophet (peace be upon him) and the sayings of the Companions as evidence. Scholars like Ibn Taymiyyah and Ibn Uthaymeen have issued fatwas affirming the permissibility of making up these supererogatory prayers whenever they are missed due to an excuse, even if they are the pre-Fard supererogatory prayers, and they are made up after the obligatory prayer or after Asr.