None of your styles beside prosilver & subsilver2 should be updated by the auto update; if you are using a style beside those 2, you have to do it manually using the code change. If you have not been updating your styles with the other updates then you are behind. I only had a phpBB forum since 3.0.7-pl1 (moved from myBB in October of 2010) and I have RedSteel & ExtremeDark Red prosilver based styles and I had to update them when we moved to 3.0.8, then 3.0.9, then 3.0.10 Manually each time using the code change.
I don't think it explains it enough since there should have been an added announcement about looking at the code change to manually update your non prosilver & subsilver2 styles!
@Volksdevil, look at previous versions on the right and go back to the last time you updated your style and all the updates will be there.