Cars registered between 2001 and 2017 according to my vehicle its 276gm CO2 so yes after April its £600, so I will get 1 year at £340 as my renewal is in march, then after that it will be £600 I presume. As mine is a Y26SE 2002 vauxhall omega CD
To clarify, vehicles with a higher g/km reading, but registered before March 2006, are placed in the K* Band. This is because it was argued at the time that somebody who purchased a vehicle with a higher g/km figure in 2004 for example, couldn't possibly have known that they were going to whack the road fund licence up two years later, hence it was not fair. Anyone that purchased a similar g/km vehicle registered after March 2006 would have/should have been aware of the higher tariff, so would end up paying the higher price.
K Band was created for this type of instance, including vehicles over 225g/km such as a V6 Omega, hence the * next to it.
Don't worry, you will not be paying £600.
.... Well, not for the foreseeable at least.