The reason we have daylight savings is due to the rotation of the earth as it orbits the sun. In March every year the rotation speeds up and in October it slows down - hence why we have to put our timepieces forward and back. If we didn't then from March to October the days would be 23 hours long - not 24. But it definitely should be done on the same dates each year and since England has the prime meridian (UTC 0), I suggest that my country's DST dates are used globally. There was a parliament bill here to abolish daylight savings entirely but it got rejected.