According the cinemark website: "Platinum Supersaver Valid for any movie, any time. Valid for one box office admission. Additional premiums may be applied for specially priced films and/or events which are priced higher than normal box office ticket pricing. May be redeemed at any participating Cinemark Theatre nationwide and does not have an expiration date. Present at box office. This ticket is non-refundable. Not redeemable or exchangeable for cash." You should be able to use these Platinum tickets for any regular show at this location.
You can walk up to pick your seat from those still available.
We use the tickets that we have bought other places (like Costco) at this theater's box office. We almost never use online reservations. However, it helps to buy the tickets in advance if you don't want to take your chances with which seats will be available close to showtime.
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