Players can play a scenario more than once (this may be necessary if we find ourselves with an uneven number of players, or if someone is not available to play in a given round etc, but also you might just fancy playing more than once a month). Where this occurs any casualties and treasures are resolved as normal but you only gain 10% of your earned experience (rounded down the nearest 5 points). Also, no matter how many times you play a scenario you can gain no more than 50 extra experience points in total for any given scenario.
This, and all other house rules can be found on the Campaign Page.