He does not stand, until when he sees the Messenger of Allah ﷺ has come out, he gives the iqamah for the prayer when he sees him.¹

The hadith of Jabir ibn Samurah is a hasan hadith,² and the hadith of Simak we do not know except through this chain.

Some of the people of knowledge have said likewise: the mu'adhdhin has more right to the adhan, and the imam has more right to the iqamah.

36 - Chapter: What has been reported regarding the adhan at night

201 - Qutaybah narrated to us, he said: Al-Layth narrated to us, from Ibn Shihab, from Salim, from his father, that the Prophet ﷺ said: "Indeed, Bilal gives the adhan at night, so eat and drink until you hear the adhan of Ibn Umm Maktum."³

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¹ Its chain is hasan due to Simak ibn Harb, for he is truthful and has good hadith. Muslim (606) and Abu Dawud (537) also narrated it, and it is in Musnad Ahmad (20804).
² In the edition of Shaykh Ahmad Shakir it appears as "hasan sahih," but the word "sahih" is not found in any of our manuscript copies, nor in the commentaries of Ibn Sayyid al-Nas and al-Mubarakfuri, nor did al-Hafiz al-Mizzi transmit it in Tuhfat al-Ashraf 2/149.
³ Its chain is sahih. Ahmad (4551) and (5285), al-Bukhari (617) and (620), Muslim (1092) (36) and (37), al-Nasa'i 2/10, and Ibn Hibban (3469) and (3470) also narrated it.
The author will soon mention the narration of Ubaydullah ibn Umar of it, from Nafi', from Ibn Umar, and its takhrij will come there.