I'm seeing some hang reports for my app in the Xcode organizer that boil down to [AAAttribution attributionTokenWithError:]. The docs for that method talk a lot about a request to Apple's services, but it looks like that's about passing the fetched token up to be decoded...but is the method also making a network request? Or is it doing something else that shouldn't be done on the main thread? If it wasn't main-thread safe I'd expect it to be documented as such, or for the Swift version to be async...
