Pokémon Sleep has announced details about the October 2023 Good Sleep Day Event which takes place from Saturday, October 28th, 2023 to Tuesday, October 31, at 3:59 a.m.

The Third Good Sleep Day Event

A Good Sleep Day event will begin at 4:00 a.m. on Saturday, October 28! Rest your very best on the night of a full moon! This event will be held once a month for a total of three days: on the day of the full moon and the days before and after it. During this time period, Drowsy Power will be multiplied by 1.5, and on the day of the full moon (October 29), it will be multiplied by 2. Let’s all try to get lots of sleep during the event and research loads of Pokémon sleep styles!

Day 1: Saturday, October 28, at 4:00 a.m. to Sunday, October 29, at 3:59 a.m.​
Day 2 (the night of the full moon): Sunday, October 29, at 4:00 a.m. to Monday, October 30, at 3:59 a.m.​
Day 3: Monday, October 30, at 4:00 a.m. to Tuesday, October 31, at 3:59 a.m.

How to Progress in the Event

Participating in the event is easy! Simply press the “Sleep” button before going to sleep during the event period to track your sleep. A variety of event-related effects will be triggered during your sleep research.

— Night of the full moon (October 29) —
Drowsy Power ×2
Pokémon Sleep EXP ×3
Bonus Sleep Points +1,000

— Other days (October 28, October 30) —
Drowsy Power ×1.5
Pokémon Sleep EXP ×2
Bonus Sleep Points +500
Notes about Good Sleep Day

• [Important] Each day of the Good Sleep Day event rolls over at 4:00 a.m.
• Event bonuses apply only to sleep data tracked within the event period.
• If you wait to report sleep data tracked before the event begins, and select “Review Later” during the event, event bonuses will not be applied.
• If you wait to report sleep data tracked during the event, and select “Review Later” after the event has ended, event bonuses will be applied.
• You can only receive bonus sleep points once per day. You will not receive bonus sleep points for the second sleep session in a day.
• Event bonuses do not apply to sleep tracking during the tutorial.
• Event bonuses will be triggered regardless of which site you conduct your sleep research in.
• The effects of incense stack with Good Sleep Day effects. If you use Growth Incense on the night of the full moon, EXP gains will be multiplied by 6 (×3 from the full moon bonus and ×2 from the Growth Incense bonus).

Source: https://www.pokemonsleep.net/en/news/2742/