Adam Clarke on Acts 19:1

And it came to pass - while Apollos was at Corinth - The Codex Bezae begins this chapter differently. But then Paul was desirous, according to his own counsel, to go to Jerusalem, the Spirit commanded him to return into Asia: then, passing through the upper parts, he came to Ephesus. This addition is also found in the Latin or Itala part of the same MS., and in the margin of the later Syriac.

Paul having passed through the upper coasts - That is, through those parts of Asia Minor that lay eastward of Ephesus, such as Galatia, Phrygia, and probably Lycaonia and Lydia; and it is in reference to Ephesus that these are called the upper coasts. See their situation on the map.