Example:  

You are not limited to 14 hours of duty.   There, that is the example!

Under FAR 135.267(b), you can be on duty 20 hours with your company, but must look back 24 hrs from the planned completion of the flight for a Part 135 flight, but not for a Part 91 flight.  You can get off, go home for 8 hours and return to fly Part 91, duty time for your company, but not violating Part 135.   You won't be able to show a 10 hr rest period in 24 though, so you can't fly Part 135.  Your duty is not limited to 14 hours ever because I can end my duty at the 14th hour and still not get 10 hours of rest before coming back for the next Part 135 flight.

The regulation is not a duty time limitation!  It is a rest requirement!