The Apostles' Fast begins movably, on the Monday after All Saints Sunday, and ends fixed on the eve of Saints Peter and Paul, 29 June. Nothing holds the two ends together, so its length swings with the date of Pascha — as long as six weeks after an early Pascha, as short as a week after a late one. On the Revised Julian calendar the arithmetic can close entirely: the fixed end arrives before the movable beginning, and the fast has no days at all. Several of the New Calendar churches now fix its length by decree rather than let it vanish.
The Typikon