Historical clue formulations

• The crack of dawn — 2025-03-28
• Vampire's bedtime — 2024-10-19
• Bedtime for a vampire — 2017-02-01
• When a cock crows — 2014-05-26
• Daybreak — 2009-09-17
• Crowing cue — 2009-06-13
• Break of day — 2006-12-20
• Early time — 2000-09-24
• Dawn — 2000-08-08
• Dawn — 1996-07-26