The time when a group buying expert's purchase behavior is included in sales depends on the specific group buying platform regulations.

Different group buying platforms may have different regulations, and the calculation methods of sales may also be different.

Generally speaking, the purchase behavior of group buying experts is included in the sales volume immediately after the transaction is completed.

That is, when the group buying expert pays for the order and completes the purchase, the group buying platform will calculate the order in the sales statistics.

This can ensure that the group buying platform reflects the actual sales situation in a timely manner and provides merchants with accurate sales data.

However, it should be noted that the specific time to be included in sales still needs to be determined according to the regulations of the group buying platform, because different platforms may have different rules.

Therefore, in specific cases, it is best to check the rules of the group buying platform or contact the platform customer service to get accurate answers.