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This player has used his vacation time again. This is the second time that he does so, while he isn't really on a holiday.
He's simply using this fuction when he runs out of time and only has minutes left on the clock. The last time that he used it, he activated his vacation time and made his move within 20 minutes.
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Instead of "Vacation" think "Auto-timeout protection".
See http://support.chess.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=31.
I think you could make a case, if you are in a completely winning position, that serial usage of Auto-timeout protection be considered vacation abuse http://support.chess.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=691 but I do not think the site could agree given this is a premium feature.
Your request for adjudication should go directly to staff. http://www.chess.com/forum/view/tournaments/how-does-arbitration-work
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