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"round 6 deadline will be friday the 12th at 11:59PM gmt+1 - rounds will start being 5 days long as oppose to a week long due to the circuit playoffs being soon" i can't make it clearer than this
if go0d can play a bit earlier for instance on friday (i can play between 11am-5pm gmt-4), then everything is alrighty. but if not, then i dont see this series getting done before deadline so the options are extension or coinflip.