Probably more a financial decision than a Max issue. We should have 60 Max planes in operation by Oct. So sure, when nearly 10% of your fleet is parked in a parking lot in a political hit job you have to do what you can to keep the rest of the operation flowing. So mgt prob looked and saw EWR as something they could sacrifice due to poor financial numbers.
Also allows those planes to be redeployed to more lucrative markets like HI, etc.