Hi, push e-mail (stock app) from my Echange 2016 server (2 mailboxes) is significantly delayed (15-30 minutes) on both my iPhone 7 and 8 when I have Wi-Fi and mobile data enabled at the same time (iOS 12.0.1). However, when I have only one of them enabled (either Wi-Fi or mobile data), e-mails are pushed and synced more or less immediately. Is this expected performance? Should not e-mails be pushed and synced just as fast and immediate when having two internet connections active at the same time?