Ahead of the official draw ceremony on 21 July 2016, in Munich, the number of participating teams was increased to 49 and the qualifying rounds were again revised to accommodate 25 teams.
Înaintea ceremoniei oficiale a tragerii la sorți de la 21 iulie 2016, de la München, numărul echipelor a fost crescut la 49, iar etapele preliminare au fost modificate pentru a include 25 de echipe.