Originally set for Easter weekend (April 11-13), it was one of three European Tour events to be postponed due to the Coronavirus pandemic.
It will now be played between July 31-August 2 and it will replace the Players Championship weekend set for then.
This means now that all three events which had to be cancelled as of writing have now been rescheduled with only Players Championship events to be changed.
European Darts Grand Prix (ET2) - now May 29-31
German Darts Grand Prix (ET4) - now July 31-August 2
European Darts Open (ET3) - now August 7-9
https://twitter.com/pdceurope/status/1240277313356521472?s=21