• Wait that all tickets assigned to Milestone v0.8.0 are closed.
• Create the next milestone
• Create the next release ticket : Release 0.9.0 #349
• Set date of the release in CHANGELOG.md.
• Create and merge PR from develop to master.
• Create the release
• Close the milestone.
• Publish the release.
• Tweet the release from @PHPOffice account.
• Contact tickets assigned to Milestone "Waiting For Answer".

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