“…The Guardian wishes me to inform you that the festivals
of the Declaration of the Báb and the birthday of ‘Abdu’l-Bahá
referred to in that passage as having been celebrated on the
twenty-second of November, 1925, by the Bahá’ís of the Orient,
are based on the lunar calendar. For this reason the date of
the celebration is not fixed, but shifts every year. Eventually
as the Master has explicitly stated, a uniform system will have
to be established by the International House of Justice.”