Starting from 2017.2.0a2 when you spawn Networking object (spawnable object) and call Destroy() in Awake method - it gives error

Could be not Multiplayer problem... but happens with spawned objects (using Networking)

How we can reproduce it using the example you attached
1 Open attached project
2 Open scene Offlinescene
3 Press Play
4 Press "Lan Host" button
5 Press "S" key on the keyboard

Actual result:
error appears
"Destroying object "Capsule(Clone)" is not allowed at this time.
UnityEngine.Object:Destroy(Object, Single)"

Expected result:
it was always allowed in previous versions, so probably should be allowed in this build as well ...