I'm using the addItem function (/portal/sharing/rest/content/users/portaladmin/addItem) to attempt to migrate layers from one environment to another, like if I were to promote content from Dev to Staging or to Prod. I'm using addItems because the other processes do not work for referenced feature layers, only hosted. https://developers.arcgis.com/rest/users-groups-and-items/add-item/#example-usage
I am trying to specify a feature service and itemIdToCreate, so the itemId I'm passing is from the Dev Portal, therefore I know the 32 character string is valid. Why is this not working? Or what am I doing wrong? My Enterprise version is 11.3 and the feature was supposedly introduced in 10.8.1.
