Steps to reproduce:
1. Open "RPCTest repro" project
2. Open "Test" scene
3. Play in editor
4. Press 1 to start hosting
-- Notice that Player(Clone) prefab is instantiated
5. Press Space to call ClientRpc
-- You will notice that "Rpc Arrived!" message was logged in console
6. Press 2 to stop hosting and press 1 to host again
7. Repeat step 5

Results: ClientRpc wasn't called after restarting host session

Reproduced with: 5.4.0p1, 5.3.5f1, 5.3.6f1
Not reproducible with: 5.5.0a5