title: TFS Migration from 2012 & 2017 to 2017
body: <p>We have to upgrade TFS version from 2012 to 2017. The problem we are facing is we have some team projects in TFS 2017 lower environment and some team projects are in 2012 production instance. We want to migrate 2012 team projects and 2017 team projects to a new TFS 2017 production instance under one team project collection. We need some help in defining the upgrade/migration strategy keeping this scenario in consideration.  Please let us know if someone can lend help. </p>