A while ago I bought several TV Shows in iTunes. These are 'Top Gear' and they show up in iTunes separated according to the Series.

Today I bought the new Christmas Specials. These show up in the same section as the other 'Specials' episodes, despite having a different series name and a different artwork.

If I edit the Artist name in 'Show Info' I can get them to separate, but they still insist on showing the artwork from the other 'Specials' series instead of their own series artwork. If I click on either of the episodes the correct artwork is shown but not for the whole series. That still shows the artwork from the Specials.

As far as I can tell, everything in the 'Show Info' is either the same as all of the Top Gear shows or distinct from the data for the original 'Specials' series.

Why do they insist on showing the wrong artwork and only show in a distinct section if I edit the Artist name?