I have a 2018 i30 CRDi and they have changed the service intervals back to 12 months/12,000 miles.
Before then, if you did less than 10,000 miles a year they recommended you had the oil changed every 12 months, but not a full service.
I wonder if over time they realised that 20,000 miles between services was causing issues and it cost them a lot in warranty repairs, so they have gone back to annual services as mandatory again?