they said it's case by case, not an error.
When's your PD? I have the same situation, called USCIS
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                    我的PD是05年12月,这跟PD有关系吗?
                     -东杨杨- 
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                        09/07/2009 postreply
                                                17:12:12
                    
                    
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                    They said if PD date too close then 1 year EAD.
                     -nickie- 
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                        09/07/2009 postreply
                                                19:38:24
                    
                    
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                    Write to USCIS...
                     -gigibaba- 
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                        09/08/2009 postreply
                                                07:35:16