Under Jobs/Tasks, Software, Patch, Import Patch Data for windows, microsoft, what do you have selected? If you only select XP, those should be the only bulletins that data gets downloaded for. Check that task schedule to see when it runs next, mine runs daily at 2am, but you can set it off manually.
Run that, and then I'd run the Check Software Patch Integrity job with "delete packages no longer in use" checked just as cleanup measure.
Note that selecting XP in the Import Patch data area doesn't mean all XP bulletins are downloaded, just that the data will be available under actions - patch remediation center. You still need to stage/distribute the patches you want to send out.