Advertisement.isInitialized always false in Editor even when enabled in Services

We use the built-in Unity Ads in multiple projects and have no problems, until now. We have a new project that has the exact same code but this time Advertisement.isInitialized remains false in the Editor. As far as we can tell everything is setup correctly.

We have found that if we manually call Advertisement.Initialize then that fixes the problem - however, we have Ads enabled in Services so we should not require to make that call.

And, I've just found the problem is there in the iOS...

Advertisement.isInitialized always false in Editor even when enabled in Services