Unable to use Custom IOS Icons (icons always replaced with unreal logo, even after replacing in /Graphics folder)

Ok, try as I might, I am unable to get custom app icons to show up on iOS.

I am using a blueprint-only project. I have replaced all icons in Engine/Build/IOS/Resources/Graphics, and all are named appropriately. In project settings, the custom icons are visible in place of all the default Unreal icons. But when I package the project, the .ipa file contains the default icons, and the app installs to an iphone with the default icon.

I’m at a loss here. Been looking around for a solution, but the solution seems to be either “remote build” (not currently an option for me, though hopefully will be soon), or “replace the icons in the Engine folder”, which I have done. There is also word that this was fixed back in 4.18 (I think), so perhaps I’ve made some small mistake? Or is this just a bug?

Thanks for any and all help,