You can manually enter your sleep data up to 30 hours after the sleep session occurred.
To do so, select Add Sleep Data from the Main Menu.
You won’t be able to perform sleep research, but you’ll see the following effects:
・ Your helper Pokémon will recover Energy according to the amount of sleep time you entered.
・ The next time you get a Bonus Biscuit, you’ll get one extra Bonus Biscuit as well.
・ Premium Pass subscribers will receive 100 bonus sleep points.