it seems you are missing a couple ones
see Setting mobile application properties, search “iOS launch images”
yes, by April 2020 your app will certainly get rejected if it does not follow Apple guidelines
in January 13, 2020
Apple news posted a remainder
Building Adaptive User Interfaces for iPhone and iPad
January 13, 2020
Apps should look great on all models of iPhone and iPad, regardless of display size or aspect ratio. With features like Xcode storyboards and Auto Layout, your app’s interface elements and layouts automatically fit the display. As announced at WWDC19, starting April 2020, apps submitted to the App Store must use an Xcode storyboard to provide the app’s launch screen and must have an interface that supports any display size.
Support for Multitasking on iPad is strongly encouraged. Adding support for multiple windows, and adopting Multitasking capabilities, including Slide Over, Split View, and Picture in Picture, will ensure your app delivers a modern and complete experience on iPadOS.
Learn about designing adaptive interfaces
Learn about multitasking on iPad
imho what you’re experiencing is the classic letterboxing because some launch screen sizes are missing
see Adapting to Changes in Context