Renaming a channel isn't applied to all areas that the channel name is used.
Original Name: "Test Renaming"
New Name: "Test Renaming1"
Areas that the old channel name continues to appear.
- Under the Files tab
- The backend folder of the channel
- The url used for "Open in SharePoint"
Thanks for showing this bug so clearly. We are dealing with as well in our organization and it is generating a lot of frustration and confusion.