Think the manual says "avoid prolonged operation above 7,000 rpm".
I tried to stay above 6,000 during break-in (very hard on these engines to "lug" them down). They're built to run at high rpm. Don't be afraid to take her to 10,000 or more momentarily - just don't cruise at 9,000 for ,more than 10 min.
Suppose it depends on your definition of "prolonged operation" is.
I prefer to break the rings in fast - few runs each from 3,000 to 6,000 WOT, then use engine braking to come back down.
Did 3-6,000, 3-8,000, 3-10,000. Important to use engine braking to help seat the rings. Baby it, and you could end up glazing the cylinders, and losing power = pull the jugs and rehone the cylinders + new rings.
Just my opinion, but worked for all my bikes including a KLR650, which are notorious for burning oil.