Reading on other forums it's a bit of a mixed bag with some doing it at 3k which is a bit overkill, to some leaving it to 20k as described by Vauxhall long life.
If petrol and only doing short runs like 5k a year id change it every year without fail due to condensation, same again if you lived in colder climate id be doing it every 6 months.
As this is in warranty it's done every 12 months at about 12k miles, at next year when it's out it will be done at every 6-8k regardless and using vx own or millers.
At work our cummins engines get frequent changes these diesels do 500k this way.
Do you leave it and do it at what mileage?
Or regardless every 6 months or 12 mths?
Or just top it up between services?
The engine needs clean fresh oil or it dies..........
Old oil blocks turbo pipes and bearing failure so clean oil and it works.