ADMIN UPDATE: not suitable solution (see why in first answer)
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Technique A:
You are automatically disqualified from that game's season if it is your turn to move in N outstanding Arena tables of that game when the season ends.
If N is 1, then some players may be unfairly penalised just because it happens to be their turn when the season ends.As N increases, more Technique A cheating becomes possible. So there's a balance to be struck (perhaps N=3?)
[Yes, I can see that this may incentivise Technique A cheaters to make last-minute moves in their losing games. There may be other ways of addressing last-minute movers].
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Technique A:
You are automatically disqualified from that game's season if it is your turn to move in N outstanding Arena tables of that game when the season ends.
If N is 1, then some players may be unfairly penalised just because it happens to be their turn when the season ends.As N increases, more Technique A cheating becomes possible. So there's a balance to be struck (perhaps N=3?)
[Yes, I can see that this may incentivise Technique A cheaters to make last-minute moves in their losing games. There may be other ways of addressing last-minute movers].