oil used in 2003 A4

At a recent oil change the Audi service mgr told me that the oil used in my 2003 A4
is synthetic or a synthetic blend, which allows it to go 10,000 miles between changes.
They asked if I was going to change it every 5k or 10k miles, and apparently would
use different oil depending on my answer. The change is covered under the 4-year free
maintenance agreement so $$ probably isn't a motivating factor.

What oil is used from the factory, and do they really use a different 10k-mile oil?

Thanks,
Bob
2003 3.0L A4Q-M