Eggman,Like Dazz I'm a convict,I to have never understood the servicing periods you have over there,personally I would be mortified if I left ANY of my cars that long before a service,but general rule of thumb is Millage or time,like Dazz said which ever one comes first,used oil does degrade even when not being used.
Service is far different over here,the Missus and I bought two 2011's(in 2011)the initial services on both where at 1000K's(625 miles)
Then to keep our warranty we must have the cars services at 15,000 K intervals (9375 miles)
We can choose too,do interim services which is just oil and oil filter at 7500K intervals(4687.5 miles)and a good visual check of the vehicles, I personally choose do do this,some may think this is overservicing,but I do a lot of Highspeed country driving,plus use my cars for towing,I have only missed one interim service on one of our cars,simple reason I got lazy and also forgot.
Even forty odd years ago when we did use milage as a service period,any vehicle's I had,whether car,truck or Motorcycle,was never left any longer than 5000 miles
All I can really advise here is do a search of the servicing section and speak to some of the English members,I would certainly hope that your dealer would notsteer you in the wrong direction,if they are a reputable dealer,if this was the case I would say you would have legal rights to take action against them and or Hyundai if they are a registered Hyundai dealer,in the case of a warranty claim,but in the three years and 110,000 K (68,750 miles ) we have been driving ours we have had very few and very minor (in my opinion) warranty claims,most being on the first car we bought and to be honest I think they were in direct relation to an accident I had in it when it was four days old,Hyundai never disputed any of the warranty fixes.
Please let us know what you find out