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The maven-release-plugin will ask you to provide the version number of the next development version (use the new minor version, not the suggested patch version). Afterwards, a new branch will be created and the version number in dev is increased to the next development version. All changes will be automatically pushed by the plugin.
In the release branch (and afterwards also in the updated dev branch, update the sp.version property in the maven archetypes (in the archetypes folder, all pom.xml templates in src/main/resources/archetype-resources)
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