with city+spirited driving we should be changing oil at 7k km max. especially on modern engines. if the oil temp and pres are within range during high rev driving after 4k old then the current oil should be stable enough. keep monitoring it up to 7k km. most oil(even some expensive ones) breakdown after being driven hard, with high temp making them lose viscosity, plus our high heat weather stretching 30 weight oil thin before 5k old.

not sure whats the highest oil temp a skyactiv could withstand. but it runs hotter than most other run of the mill japanese budget-car engines. ideally on a road, car we shouldnt let the oil go above 135c. a typical 5w-30 and 5w-40 oils would be done at that temp.

for semisyn, it is best to change it every 6 months even when not driven much as they lose their properties earlier than fullsyn