Actually in a previous on-site support we have discussed this issue. It has been revealed that Unreal had been working on a seamless cross-DS travel mechanism to support a bigger seamless server world consist of multiple Dedicated servers of the same map, with each one them hosting an individual subregion. Theoretically seamless travel between Dedicated servers of the same map, without reloading the map on Client is possible.
What we have wanted is travelling from DS to standalone, and then backwards. This is hard and a map reload is inevitable due to the fundimental differences between a client world and a standalone one. We need to create a GameMode for the standalone world, recreate and reinitialize almost every actors and WorldSubsystems for the world for their logic (or even if the subsystem should be created or not) may vary in two net modes. So we totally understand we need to go through the LoadMap process. We have also figured out how to retain the player pawn and camera state from the old world and transport them to the new one.
But since the level map and streaming source location is the same, we were wondering if it is possible to protect the consistent resources from GC, so we do not need to reload them again afterwards? As a trial, I plan to make an reference UObject, make it refer all the loaded streaming levels and add it to the root, then unref the levels and delete the object after the new world has flushed its streaming state. I do not know if it would work, or is there any more efficient or maybe more formal way to do this?
Thx