Notes & justification
Yaʿqūb, when he stops on عَمَّ, adds the hāʾ of pause — عَمَّهْ — and so does al-Bazzī (Ibn Kathīr's first rāwī), by one of two transmitted wajhs. The table prints no cell for it because it concerns only a pause, and عَمَّ is not a place to stop. The Shāṭibiyyah line names the words فِيمَ، مِمَّ، عَمَّ، لِمَ، بِمَ as taking the hāʾ in the pause for al-Bazzī bi-khulf; the Durrah lines give the hāʾ to Yaʿqūb (the ḥāʾ of حُمْ is his code) in يَا أَبَتِ and in these interrogative words, and extend it to the rest of the group as for al-Bazzī.
Stop on fīmah, mimmah, ʿammah, limah, bimah — with khulf from al-Bazzī — and turn away whoever calls it ignorance.
… and stop on yā abah with the hāʾ — (Yaʿqūb) — and on lim, sweetly.
And the rest of them (are read) as al-Bazzī, together with huwa …
Yaʿqūb used to add the hāʾ of rest to عَمَّ when pausing. This is not a place to pause; it is mentioned only so that his practice is known. The justification: the word is originally عَمَّا — the preposition عَنْ prefixed to interrogative مَا; the nūn was assimilated into the mīm, giving عَمَّا, and then the alif of مَا was dropped to distinguish the interrogative مَا from the relative, leaving عَمَّ. When they pause on عَمَّ they add the hāʾ of rest so that the fatḥah of the mīm is kept as it is. One does not stop here; the ruling is given for the case where it were allowed. (al-Mūḍiḥ 3:1331)