Historical clue formulations

• Seemingly for-EH-ver — 2026-09-23
• 1,000,000,000 years — 2026-09-13
• Vast span — 2026-07-12
• It's one for the history books — 2026-06-21
• 1,000,000,000 years, in astronomy — 2026-06-18
• It literally takes ages — 2026-06-15
• Forever and a day — 2026-06-03
• Forever and a day — 2026-01-06
• Time unit aptly hidden in "paleontology" — 2025-10-20
• Proterozoic, for one — 2025-08-06
• Phanerozoic, for one — 2025-07-11
• Many, many moons — 2025-06-29
• Eternity — 2025-05-11
• Long spell — 2025-05-03
• Long, long time — 2025-04-07
• Long time — 2025-03-18
• Ages and ages — 2025-02-19
• Equivalent of a billion years, in geology — 2025-02-16
• Long, long time — 2025-02-09
• Ages and ages — 2024-12-24
• Seemingly forever — 2024-12-11
• Long time — 2024-11-27
• Vast span — 2024-10-18
• Very long time — 2024-08-13
• Long, long time — 2024-08-04
• Forever and ever — 2024-07-28
• One of four in Earth's history — 2024-07-25
• Many, many years — 2024-07-21
• Many moons — 2024-06-23
• Immeasurably long time — 2024-06-03
• Seemingly endless time span — 2024-05-27
• Big stretch — 2024-05-01
• Long stretch of time — 2024-04-29
• Ages upon ages — 2024-04-28
• Ages and ages — 2024-04-22
• Lo-o-o-ong time — 2024-03-07
• Seeming eternity — 2024-02-11
• Over time period? — 2024-01-21
• Long, long time — 2023-12-14
• Very long time — 2023-11-21
• Many lifetimes — 2023-11-02
• Seeming eternity — 2023-08-31
• Ages and ages — 2023-04-19
• Forever and a day — 2023-03-08
• Many millennia — 2023-01-29
• Very long time — 2022-11-29
• Ages and ages — 2022-11-28
• Big time — 2022-10-20
• Phanerozoic ___ (what we live in) — 2022-10-16
• Stretch longer than an 11-Down — 2022-10-09