Obtain 3,000 tier (base) points in a gaming day (varies property to property); and you will be upgraded to Diamond.
The 'official word' from Caesars Entertainment, regarding PIAD AND DIAD at the Atlantic City properties :
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In regards to the second email that you've sent to us, I'd be glad to assist you with the Platinum and Diamond in a Day Promotions. To participate in the Platinum in a Day promotion, simply earn 2000 base credits during one gaming day. For the Diamond in a Day,simply earn 3000 base credits during one gaming day (6am-5:59am) at any of our Harrah's Entertainment owned casinos in Atlantic City. Please know that in order to participate all base credits must be earned at one casino (earning 1500 at Bally's and 1500 at Caesar's will not qualify you for the promotion). We certainly hope that this information proves helpful.
