How experimental is the overrideSharePermissions query parameter?
I gave it this edit permission:
"editPermissions" : [ { "type" : "project", "project" : { "id" : "10027" }, "role" : { "id" : "10002" } }, { "type" : "project", "project" : { "id" : "10027" }, "role" : { "id" : "10016" } } ]
And it ended up only shared to the project (Everyone) instead of the two specific roles I've given.
If I use the UI to edit, then I can share to those two role ids.
Is role assignment not implemented in the REST API yet?