World Partition load screen 5.4

Hi,
does someone has any info of the default loading screen while using world partition?
At level start we have a black screen with a bobber at the lower right corner, this is nothing we added anywhere, so it should be something epic has never communicated anywhere?

The real question would be, how can this screen be changed or even prolonged?
As the player is sometimes loaded before the world around was completly loaded!

Greetings