I can make neither heads or tails over successfully saving a change to a session WITHOUT having to save a new route.  
I just went into surveyor mode with a session, edited a portal to output trains, making sure that it was in the session layer, but when I attempted to save the session, the game requires me to name a new route and session.
Other times I've been able to save sessions only, without touching the route. There just seems no pattern.
Can someone please explain?
				
			I just went into surveyor mode with a session, edited a portal to output trains, making sure that it was in the session layer, but when I attempted to save the session, the game requires me to name a new route and session.
Other times I've been able to save sessions only, without touching the route. There just seems no pattern.
Can someone please explain?
 
	 
	 
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