Question about Poly Voyager Focus UC B825-M

Bluetooth: Does the headset connect directly to the mobile phone or via the charging station? Background to my question: I bought the Poly Savi 8220 Duo and found out that the connection from the mobile phone goes to the cradle and from there to the headset. I.e. if one cannot use the headset e.g. on the way, because the station must be present and must have current. This would not be the case with a direct mobile phone-headset connection. That was all with Bluetooth.