We have a inaccurate subrelation that was set up in SiteCatalyst14. When trying to disable the subrelation within SC15, it doesn't override the SC15 settings. I am not able to turn off subrelations in SiteCatalyst15 because everything is automatically subrelated out of the box.
A future enhancement would be to have the ability to disable a subrelation within SiteCatalyst15 so users don't have the ability to build inaccurate reports.