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Circadian day map

Your protocol in miniature: one wake-time anchor expands into the behaviors that usually move sleep quality.

One pass through the Dusk-style pillars: we infer bedtime from your wake time and chosen sleep duration, then place light, stimulation (caffeine), food, temperature, and sleep anchor around that rhythm. Tune sleep length if your diary differs.

Anchor

Target bedtime → 23:00 (wake − 8 h)

Approximate DLMO reference (rough): ~2 h before onset → 21:00

Morning light

Bright outdoor or high-lux indoor light soon after wake: 07:0009:00 (first ~2 h). Anchors circadian phase for the rest of the day.

Caffeine cutoff

Gardiner-style gap (8.8 h + no extra) → finish caffeine by 14:12 (8.80 h before bed).

Eating window close

Aim to finish substantial calories ~3 h before bed: by 20:00. For a ~10 h daytime eating window (time-restricted eating framing), a plausible open is around 10:00 — adjust meals to what you can sustain.

Pre-sleep temperature drop

Warm bath or shower 1–2 h before bed can promote distal heat loss after: roughly 21:0022:00. Start cooling the bedroom toward 22:30 (thermoneutral preference varies).

Educational estimates only. Sleep and caffeine metabolism vary widely. This is not medical advice; talk to a clinician if you have insomnia, apnea, or other conditions.