Yes, a "S" split radio will go as high as 512mhz. Though, there isn't much up that high in most areas, congested areas such as high population cities will probably use frequencies up that high. Technically speaking, all HT1250's can DO 403-512mhz its just a matter of reliability of the RF section of the radio, since 403-470mhz radios aren't designed to be used up that high, problems such as poor Rx, poor Tx or VCO unlock can occur, and visa versa. Of course, this is not to mention the firmware and codeplug modifications that need to be made to force the radio to do the different split.