The COVID-19 forced a halt to football and therefore a restructuring of the calendar. Both the Champions League and the Europa League will have to wait until the summer.
UEFA's plan is for the Champions League to return on the first weekend in August. Marca assures that City-Madrid will be held on August 7. On the same day Juventus-Lyon will also take place. On Saturday 8th Barca-Napoli and Bayern-Chelsea will play.
That's not official yet, but it's the plan to follow. UEFA has yet to ratify it and will do so before the end of May. The Executive will meet on the 27th and set the final dates. In any case, everything will depend on the pandemic and its evolution.
The clubs have time to prepare. There are three months left to listen again to that Champions hymn that makes everyone's skin crawl. Before that, they must finish the domestic tournaments.