Session Duration
This is the estimated time the session will run.
This will vary according to the progress the party make.
The GM MAY allow a session to extend beyond this duration if they, and the players, agree.
One shots
These are a specific case. It is difficult to judge some group’s progress so it is possible you may not complete the adventure within the alotted time. GMs will try to ensure you do complete the adventure but inevitably some parties will miss.