troubleshooting the issue at this time may cause more harm than good.
How could diagnosing the symptom cause more harm? IMO what is needed is clarity about the symptom.
Care to share the link to your Feedback? Currently a search there (in the non-Insider Feedback) using Category: Install and Update Subcategory: Windows Update Sort: Most recent and your details: 1809 black screen zeion finds one which says: "Everything went great!" ; )
HTH
Robert Aldwinckle