Will X1 Challenge unlock at B-Spec 30?

[Apollo33]

I'm currently grinding to Level 24 in A-Spec and saving for a Formula GT, but reading about these endurance races is really making me reconsider my will to get to the X1! Does anyone know if getting to Level 30 in B-Spec would open the X1 Challenge? It would be so much easier to have my Bob do endurance races while I'm at work and while I sleep!

 

[KlosterKatten]

Yep, everything else unlocks with both A & B-spec, so b-spec will be fine.