The question arose: When was Janmastami? Our calendar, put out by Pradyumna, said it was one day in the West and a different day in India. By astrological calculation he had worked out the world in time zones, and those who lived West of a particular time zone would observe it on the following day. Seeing the confusion, you said the calculation was "over-intelligent," and whatever day it was celebrated on in India, it should be celebrated the same day all over the world.
(From Vipramukhya Swami's Vyasa-puja offering to Srila Prabhupada, 1986)