Complex sentence: The time limit was always a multiple of 5 seconds, usually at least 30 seconds; at one point Collyer said that a 55-second time limit was the maximum, but later on, stunts occasionally got 60-second limits.
Split into simpler sentences: The time limit was always a multiple of 5 seconds, usually at least 30 seconds. At one point Collyer said that a 55-second time limit was the maximum, but later on, stunts occasionally had 60-second limits.