I have a Quick Start RDS deployment on one host under Windows 2012R2, domain member. I applied group policies on this host that limited sessions timeouts:
Windows Components/Remote Desktop Services/Remote Desktop Session Host/Session Time Limits:
End session when time limits are reached Enabled
Set time limit for active but idle Remote Desktop Services sessions Enabled
Idle session limit: 1 hour
Set time limit for disconnected sessions Enabled
End a disconnected session 1 hour
Gpresult shows these settings are applied successfully, and the server drops the sessions according to the settings.
When I go to
Server Manager\Remote Desktop Services\Collections\QuickSessionCollection proprties I can see 
Time outs are set to never.
Why I don't see the actual settings here? Is there something similar to RDP-TCP properties in 2008 R2 server?
Where I can see the settings set by GPO.
Best Answer
You must configure the Session settings with the Session Collection settings dialog (your first screenshot) and the session hosts will reconfigure to match your selection.
You shouldn't tweak the settings with a GPO.
I highly recommend you to disable/remove the GPO that you created, and reconfigure the settings that you want within the Session Collection properties in Server Manager. When you'll hit the "Apply" button, Server Manager will configure remotely your session hosts (hence the delay when you click "Apply")