When the time changes in the spring and fall due to the start or end of Daylight Saving Time, your sleep record will still maintain accuracy. The app will show your bedtime and morning wake-up time as they align with the world clock. You will notice in your sleep chart that on the night of a time change, the app will record two 1:00 AM time slots. Essentially, just as the clock hits 2:00 AM, the sleep chart record then rolls back to 1:00 AM. Rest assured you are not losing this recorded time asleep, as it is still being recorded as 2 separate hours.
Because of this, your sleep record will show your correct sleep duration. You are not required to do anything differently when tracking: the app factors all of this in automatically.