You don't specify how you drive the car or even what car is involved, so it's a bit of a guessing game.
However, unless you have something really highly tuned or one of the badly implemented, heavy fuel diluting GDI engines, or you really beat the snot out of the thing all of the time, or you have really severe operating conditions, 6K is a piece of cake with any synthetic oil and probably most conventionals.
Does your car have an OLM?
If it does, you could just follow it for OCIs, secure in the knowledge that for most engines and most users, its calibration is pretty conservative.