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These tasks are not necessarily exclusively done by the release manager. The community should take care of it. The responsibility of the release manager is to make sure that a certain quality and stability of the relevant code base is achieved.
Additionally, any release-related documentation should be kept up-to-date (e.g. Release Management and Feature Plan or Creating a Flink Release)
Organization
Regular Sync
It's a good habit to meat on a regular basis to sync on the developments of the current release cycle. A summary should be kept in the release's wiki article (see Release Management and Feature Plan) and sent to the dev mailing list to keep the community up-to-date.
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