When using ArcGIS Pro to publish enterprise geodatabase feature classes as web layers, many properties are included in the resulting feature layer in Portal (e.g., pop-ups, definition queries, and symbology. If a refresh interval is set in Pro, it does not become a property of the feature layer. Also, the property must be set again each time the feature layer is republished.
Of course someone can write a script to publish the web layer and set this property in Portal, but it seems like an oversight when so many properties carry forward during publishing.