To get your instrument rating you have to do a similar flight, except
one of the legs only has to be 200NM straight line and its dual. When I
did mine, me and my instructor made a stop at the second landing point
to fuel up, but when we tried to start the plane back up, it wouldn't
start. So we had to call the FBO from where we're based and they had to
send another plane over to pick us up and bring us back home. The next
day we were flown back to pick up the plane after the starter was
repaired, then flew it back to complete the lesson. I'm pretty sure
what we did was legal.