I misunderstood the question at first. I think what you’re looking for is the WRKTIMZON command. Either specify your time zone in the TIMZON() parm or scroll down through the list to find yours. Use option 5=Display details. Scroll down the details to see start/end dates/times.
General info —
First, make sure that you have a decent PTF cume package installed. By now, your cume level shouldn’t be anything below 9321.
Then, run DSPSYSVAL QTIMZON.
That will tell you which time zone is configured on your system. If you tell us your geographical location, we can probably tell you what your time zone setting should.
You might also run DSPSYSVAL QTIME.
If you tell us what QTIME value is returned and also tell us what the actual time is at your location, we can probably tell if any configuration changes should be made.
In general, if your system time is correct and your time zone setting is correct and your PTFs are appropriate, your time will change for Daylight Saving Time whenever it’s defined to change at your location.