I wouldn't go over by much maybe 50 miles at the most.It's not the type of oil or age of the oil that matters during the 600 mile break-in. You need to schedule the service a.s.a.p. During break-in, filings and shavings from inside the engine dislodge and end up in the oil. You don't want that stuff circulating in the engine! It should all be captured and contained by the oil filter and oil screen, but the mechanics need to check the drained oil to see if there are any abnormal bits in there.