I doubt it. Leg bands are ordered long before the chick hatches in most cases, and have to be applied in the nest while the chick is still quite young. I have never heard of a band having the actual date on it. My bands include the year, my breeder code, the state, and a number. The closest you will get to a hatch date in the band is usually the year, and even that can be off if lazy breeders re use bands from the year before. It is most likely that the number on your band has to do with how many chicks were produced either gat year by that breeder, or by that breeder ever, rather than the date, judging by the format. Often the year will be tipped sideways. There is no national registry of bird leg bands, but some clubs have registries. You can also look up leg band suppliers and give them a call; some of us leave permission to contact if someone calls inquiring about a bird wearing our band.