Why are half-hourly timeslots showing more than once, or missing from my online account day view?
Time slots are shown more than once when the clocks go back or are missing when clocks go forward.
Time slots will be shown more than once when clocks go back one hour in autumn for Daylight Savings (DST). On this day, two additional time slots will be displayed, and you'll see a total of 50 timeslots instead of the usual 48.
Conversely, when the clocks go forward in spring, the corresponding time slots for that hour won't be shown. You'll see 46 time slots displayed on this day.