Reproduction steps:
1. Pull the GitHub repo provided in the initial report
2. Open the Unity project (it will be connected to an Accelerator cache server)
3. In the Project window click the second mouse button to bring out the context menu
4. Go Create -> Asset Generator -> Extreme (500MB)
5. A .txt Asset will be created and the upload to the server will start in the background
Expected result: The asset is created and is being uploaded to the cache server in the background. You can use the editor for other things.
Actual result: The asset is created and is being uploaded to the cache server in the background. During the upload the editor freezes completely, after the upload completes "On demand scheduler transport error" is thrown
6. If the issue did not reproduce, reimport the created asset until the issue reproduces
Reproducible with: 2022.1.0a1, 2022.1.0a5
Could not test with 2021.2.0a21 or earlier because the feature was not yet implemented
Please check Vitaly's comment - might be the same issue or new one.