Currently issues with ArcGIS Online need to be raised through the local Esri distributor. For example, the 'Report an Issue' link on the ArcGIS Online Health Dashboard page just links to a page containing contact info for the local distributor.
This support model does not work well with services delivered in the cloud and managed/supported by Esri Inc. For example, a recent issue with online feature services was raised with Esri UK on 7th Jan and is still not resolved on 14th Jan. The main reason is that Esri Inc did not get sight of the issue until a few days after it was raised. Obviously for a customer's enterprise solution to be impacted for over a week is not acceptable.
Where the issue is directly related to an AGOL service provided by Esri Inc, we should be able to raise issues directly via an AGOL support page. Without this mechanism, I also beleive that the Health Dashboard does not provide the real-time situation, because issues are held for days by the distributor before being raised with Esri Inc.