The network IDs assigned on the VRCWorld component by the network ID tool are lost when reopening the project if that VRCWorld component is a prefab.
  1. The VRCWorld component is a prefab
  2. Running VRChats network ID tool assigns different IDs
  3. Saving the scene
  4. The new IDs can be observed on the VRCWorld component
  5. Close and open the project
  6. The network IDs on the VRCWorld component are now reverted to the state before running the network ID tool
This issue only occurs if the VRCWorld is a prefab.
Here is a video demonstrating this issue using the 3.4.0-creator-economy.5 SDK when building for Android with Unity 2019