Apps can now edit orders they created
API
Effective August 12, 2020
Previously apps could only edit orders created through a Shopify channel (for example, POS, online store, or draft orders). Going forward, apps can now edit orders they created. To determine if your app can edit an order on Shopify, you can query the merchantEditable field on the Order object. If the return value of this field is true, your app can edit the order.