Hi @Watanaphon Adomat,
Sessions are scheduled based on the Service Goal Impact:
https://help.mypurecloud.com/articles/service-goal-impacts-overview/
along with the Attendee Availability, Facilitator Availability, Session Availability constraints and minimum/maximum group sizes.
The only constraint that affects the "buffer" is the Transition Time (on the facilitator tab), which provides a "buffer" between sessions scheduled with the same facilitator so that they have a break between sessions.
In your example/experience, the 2 sessions will have been scheduled at the best start time that meets all requirements, rather than being "padded" by a set amount of time.
Paul
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Paul Wood
Product Manager for Genesys Cloud Workforce Management
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