Not surprising given it is now owned by BMI.
From https://www.aa.com/apps/AAdvantage/ViewMileageProgramsPartnerDetail.jhtml?fileName=britishAirways.xml&repositoryName=AAdvantagePartnersContentRepository&repositoryId=16019194&itemDescriptor=AAdvantagePartnersContent
Effective for travel on/after October 28, 2007, British Airways flights formerly operated by franchise affiliate BMED will be operated by bmi British Midland, and will no longer be eligible for AAdvantage mileage accrual or redemption.
From https://www.aa.com/apps/AAdvantage/ViewMileageProgramsPartnerDetail.jhtml?fileName=britishAirways.xml&repositoryName=AAdvantagePartnersContentRepository&repositoryId=16019194&itemDescriptor=AAdvantagePartnersContent