Original Message

135.263(d) A flight crewmember is not considered to be assigned flight time in excess of flight time limitations if the flights to which he is assigned normally terminate within the limitations, but due to circumstances beyond the control of the certificate holder or flight crewmember (such as adverse weather conditions), are not at the time of departure expected to reach their destination within the planned flight time.

135,267(d) Each assignment under paragraph (b) of this section must provide for at least 10 consecutive hours of rest during the 24-hour period that precedes the planned completion time of the assignment.

If you are assigned 3 flight legs, your assignment is the whole package.  And, if you were good to start the flight assignment, you are OK to finish the assignment, even if it exceeds the 10 hrs rest in 24 hour look-back from the completion of the ASSIGNMENT.   It is not a leg-by-leg assessment as was established by the Whitlow intepretation under Part 121.   The FAA was going to try and make it a leg-by-leg assessment, as the Notice of Proposed Interpretation indicated, but they withdrew it, letting it fall back to what it was, which was by assignment (not leg-by-leg).