UA22 DUB-EWR 763 (usually 764) cancelled due to an unexpected operational issue. Replacement flight UA3033 was scheduled 55 minutes later and arrived at EWR already.
UA23 EWR-DUB 763 (usually 764) cancelled due to an unexpected operational issue. Replacement flight UA3042 is scheduled with exact same departure time.
UA30 EWR-MUC 763 (usually 764) cancelled due to an unexpected operational issue. Return UA31 on 6/19 cancelled as a result. Replacement flights UA3043 and UA3044 have been scheduled around the same time as 30/31.
UA52 IAD-ZRH 763 cancelled due to maintenance after a 20 minute delay. Return UA53 ZRH-IAD on 6/19 cancelled as a result.
UA127 FCO-IAD 764 returned to FCO due to maintenance, resulting in a 2.5 hour flight to nowhere.
UA942 IAD-LIS 763 (usually 764) cancelled due to an unexpected operational issue. Return UA943 LIS-IAD on 6/19 cancelled as a result. Replacement flight UA3045 was scheduled to depart the same time but that was cancelled due to maintenance after a 20 minute delay.
UA963 BER-EWR 764 cancelled due to maintenance after an around 1 hour delay.
UA991 BCN-IAD 764 cancelled due to maintenance after a 2 hour delay.