When doing a promotion with the 'Display Overlay Page' option selected, the ‘Promotion Overlays’ panel is not being displayed. If you do the promote again and DO NOT select ‘Display Overlay Page’ the ‘Promotion Overlays’ panel is now displayed. The selection of the ‘Display Overlay Page’ option is functioning backwards/reverse of how it should work.   

Full article: https://portal.microfocus.com/s/article/KM000017289