SELECT r.session_id AS [Session_Id]
  ,r.command AS [command]
  ,CONVERT(NUMERIC(6, 2), r.percent_complete) AS [% Complete]
  ,GETDATE() AS [Current Time]
  ,CONVERT(VARCHAR(20), DATEADD(ms, r.estimated_completion_time, GetDate()), 20) AS [Estimated Completion Time]

• How many destination servers do you require?

  If you require only a single destination database, database mirroring is...

The first step you have check your applications compatibility with 2016 So in this situation mirroring is best option because with this in minimum down time you check all applications...