They are bringing back additional international flying on June 4th and again on July 1st (with EWR-EDI flight resuming then). June flights should be relatively firm at this point, while July may see some adjustments depending on much demand improves. Ultimately, alot is going to depend on how much countries have opened up by then. The airlines are currently throwing a lot of summer capacity at ATH as Greece is among the first of countries to begin lifting quarantine requirements.