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Deletion Semantics: Any offset which is eligible for expiration may be deleted even if the group is still active. Usually we do not allow committed offset changes while a group is active because we do not have a mechanism to notify the group of the change. However, offsets which are awaiting expiration do not have this problem because they are not being actively consumed. Hence the deletion can be immediate even when the group is active.

Compatibility, Deprecation, and Migration Plan

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