Similar story down under. After World War I, Melbourne built a "Shrine of Rememberence" - a lovely war memorial that included a light aperture that causes the sun to shine on the tomb of the unknown soldier at exactly 11am on 11th of November (when WW1 ended.) It was built to be accurate for over 1000 years.

Then a few years later the government introduced daylight savings..

So now they use a mirror to "fudge" the effect at the official time of 11:00am (Daylight Savings Time), and an hour later - when the official ceremony is over and the dignatories have left - the public can enter and see the effect for real at midday (11:00 am Standard Time).

Go figure..