The editable history window in MEWS provides the hotel a certain amount of time to modify accounting items in reservations. After that period the information in MEWS is final. When the EHW is set to 8 hours, the first moment in time we could run the integration is 08:01AM in the morning the next day.
Some hotels want an end of day in their integration. That means that the data we extract from MEWS is not from 12AM until 12AM the next day but for example from 2AM until 2AM. We need to take into account the end of day for the time the integrations runs. So when we have an end of day of 2AM and an EHW of 8 hours then the first moment in time we could run the integration is 10:01AM.
The reason we take into account the EHW is because we know that after that period of time the information in MEWS is final and can't be modified anymore. Then we know for sure our journal entries will always match MEWS.