This is from FAA.
The goal of flight and duty time regulations is to prevent crew fatigue. Section 135.267 establishes two mechanisms to determine applicable flight time limitations and rest requirements for flight crews of certificate holders conducting unscheduled operations under 14 C.F.R. part 135, using one or two pilot crews. Such certificate holders can assign their flight crews to a: (a) moving 24-hour consecutive schedule, in which case, the requirements and limitations of§ 135.267(b) apply, or (b) regularly assigned duty period of no more than 14 hours, in which case, the requirements and limitations of§ 135.267(c) apply. See Legal Interpretation to Daniel Berry, from Rebecca B. MacPherson, Assistant Chief Counsel for Regulations (May 22, 2009).
FAA regulations allow flight crews of certificate holders operating under § 13 5 .267 (b) to exceed the maximum flight time established in§ 135.267, if the extension is due to circumstances beyond the control of the flight crew and the certificate holder. In contrast, flight crew of certificate holders operating under§ 135.267(c) cannot exceed the rigid, maximum duty period of 14 hours allowed for in such subsection. Any certificate holder or flight crew who conducts operations under § 13 5 .267 ( c) and exceeds the 14-hour duty period threshold, violates§ 135.267(c). This is an inflexible rule, which results from industry interest in creating a standardized alternative to resolve the operational gap resulting from disruptions of flight crew utilization due to the extension of flight duty periods pursuant to § 13 5 .267 (b ).
Notwithstanding the above, the FAA will not consider the following to constitute a violation of§ 135.267(c): if the certificate holder or flight crew reasonably anticipates that the flight segment(s) can be conducted under the 14 hour threshold, but the flight is unexpectedly delayed enroute due to unanticipated events, thereby exceeding the 14 hour maximum duty time mandated by § 13 5 .267 ( c ). See Legal Interpretation to Mr. Ross, from Donald P. Byrne, Assistant Chief Counsel, Regulations Division (August 30, 1993).
Since it says segments you can finish with crew..