Other than AKV, there is no concierge service for any DVC resort including BWV or BCV. The one in AKV is in Jambo and has the sixth floor for concierge rooms and lounge and access to concierge services in Jambo including CMs at the front desk.
BCV and BWV do not share concierge with BC and BWI simply because you cannot reserve, even for an etra fee, any concierge services when staying in a BWV or BCV room. If you are simply talking about where the applicable lobby is and where you would find the CMs that can deal with concierge then BC has its own lobby and BWV and BWI have the same lobby.
Are you talking about booking a Concierge Level room or are you asking about the hotel concierge desk where you can ask questions, buy tickets, etc. If the latter, then for most of the DVC resorts attached to a hotel, you go to the hotel lobby's concierge desk. I expect Kidani has it's own and doesn't require you to go to Jambo House but I can't recall.
The standalone resorts will have their own concierge somewhere near the check-in area.
ETA: They have added a check-in desk in BLT but I don't know if the CMs there also handle concierge tasks or if you have to walk over to the CR.
Even with the DVC resorts attached to a hotel, how convenient it is to get to the lobby concierge desk varies. For example, BWV and BWI share a common lobby so it's no problem. VWL is a separate building from WL. There are no services at all in the VWL lobby, you have to walk over to the WL. For BCV you would have to go to the BC lobby. As I said, BLT recently added check-in services but I don't know if there is staff there 24 hours or if they offer any other services there. If not then you would have to walk over to the CR.
I expect AKV has a concierge desk in Kidani as well as Jambo House because they offer everything else at Kidani (check-in, Bell Services, valet parking). I think it's over on the right end of the check-in area. ETA: Just found a Youtube video of the Kidani lobby and the Concierge "desk" is at the right-hand end of the check-in area.