Delta Real Time Clock timing

Hello All.
I have a program running with a Delta DOP HMI and a Delta SA plc.
This program switches using real time clock because we often have power cuts.
The program switches lights on in the morning and off in the evening at set times.
Now I would like to switch on about 5 minutes earlier each day and off 5 minutes later each day (accumulative) To gradually lengthen the days.
Can anyone help me. I have tried but it is too complicated for a beginner like me.

delta plc programming cable diagram

I'm looking for delta plc programming cable diagram
for a Delta PLC, model DVPEH3

Thanks.