How many kilometers do you usually drive before servicing your BRZ, and what oil do you recommend?

I don't drive my car much in a year, so I only need to service it once a year. I use Mobil 1 0W-40.

I have driven 5000 kilometers using Motul 8100 0W30.

I usually get maintenance done at 4000-4500, even though it's supposed to be every 5000.

5,000, fully synthetic