I sent out my federal and DC tax forms by certified mail on April 13. My federal tax forms arrived three days later and Uncle Sam has already cashed the check. There is no record of delivery for my DC tax forms, which were being sent to a P.O. Box located in the same post office from where I mailed the forms. I suppose it's a good thing that I filed for a refund from DC and can refile anytime within three years if the form is indeed lost. This ever happen to anyone else?