The Prophet ﷺ continued to speak often about the matter of the Hour until this was revealed, "They ask you about the Hour, when will it arrive?" [Naziat 79:42]
أن النبي ﷺ كان لا يزال يذكر من شأن الساعة حتى نزلت: {يسألونك عن الساعة أيان مرسها}
No references are available.
Nasai narrated it in his tafsir (11581), Ibn Jareer in his tafsir (24/100), and Tabarani in Al-Kabir (8/387), all of them from the hadith of Ismail bin Abu Khalid, from Tariq bin Shihab, and he mentioned it. Its chain is sahih, and Tariq bin Shihab is among the junior companions, those whose seeing of the Prophet ﷺ is established but whose narration from him is not established, and the mursal narrations of the junior companions are accepted by the hadith scholars. The Prophet ﷺ then informed of the nearness of the establishment of the Hour in many hadiths, among them this one.