Client and Dedicated server on different subsystems not having a session

So, our client’s primary online subsystem is Steam, this is so we can have support of steam’s p2p sessions. However our dedicated server uses the Null system so that its not restricted to a specific platform.

When i use the console command “open” with the server’s ip address this works just fine as intended and connects to the server and plays just fine. The server also has an online session created on startup, however when i try to call anything related to sessions on the client i get errors with steam, for instance calling “DestroySession” to leave the server the client logs the following:
"Warning: STEAM: Can’t destroy a null online session

Should the client still be getting session information from a dedicated server when joining with a direct IP join? Is it possible to switch which online subsystem is being used at runtime for when a client joins an online session? I’m ok with doing engine modifications to suit this but i’m not even sure where i would start looking to call into to change this at run time.