Sharp Atomic Clock Model Number SPC 374T

Question

We recently switched to day light savings time and our clock is still reading standard time. We are set for eastern standard time which is correct. We changed the batteries today and saw the time on the clock reset itself to the correct time but it is still off 1 hour. We are wondering if this could be due to the preprogrammed DST module that is in the clock? The DST indicator is not lit up indicating that perhaps this is the case. Any suggestions?