Titus 3:12

‘When I shall send Artemas to you, or Tychicus, give diligence to come to me to Nicopolis, for there I have determined to winter.’

Paul then tells Titus to make all speed to come to Nicopolis to see him, for he is planning to winter there. No doubt he was planning a winter campaign during the period when travel by boat was impossible and wanted Titus to join him in it and update him on the situation in Crete. Speed was necessary so as not to miss the opportunity of summer travel. Meanwhile he would send either Artemas and Tychicus to replace him. Tychicus was later sent to replace Timothy in Ephesus (2 Timothy 4:12). It is clear that Paul was careful to ensure that the churches that he saw as under his care always had a responsible person there to keep watch over things, one of his travelling lieutenants. There were a number of places named Nicopolis so we do not know where this was.