I deleted my pb from XFG/BL1 combo this morning, then drove 12 quick race on multiplayer (still same combo), approx 50 laps, but lfsworld still displayed n/a - even I got (several) lfsworld messages of new PB while doing those races.

Its weird, because now after some 9 hours (and I realized it now) I joined again one demo server for testing this issue and got immediately my first lap into lfsworld as new pb (i had now lfsworld window open at same time).

Is there some transaction time after you delete your old pb, until the new one gets registered? Hmm..actually it felt more like the delete transaction has been run again later. Maybe I'm just drunk LFS fanboy