Almost four years ago, Microsoft acquired HockeyApp after having used the service internally for a period of time as part of the testing and distribution of Skype on mobile platforms. At the time, the Redmond giant left the service in situ for new and existing customers but later foreshadowed that HockeyApp would eventually be merged into a "new, next generation product" known as Visual Studio App Center but stopped short of providing information as to when that would officially conclude.
In an announcement on its blog, HockeyApp has now provided a timeframe as to when it will wrap up the migration to Visual Studio App Center, having said:
"Today, after months of work and refinement, we are announcing that HockeyApp will complete its transition fully to App Center in one year on November 16, 2019. We know you are busy building amazing apps, so we have focused on making this transition experience smooth and seamless for you."
As of the time of writing, users can get going with App Center or continue to use HockeyApp side-by-side during the changeover period. However, in "early 2019" users will be able to fully migrate their apps to Visual Studio App Center at a time of their choosing up until November 16, 2019. The act of migration will be a one-way trip, which means that you will no longer be able to sync or manage your apps via HockeyApp.
If you're interested in looking at HockeyApp's transition plan, you can check it out here. The plan also includes a rundown of parity gaps between App Center and HockeyApp and their corresponding status.