According to the Bluetooth.org the 820/920 where just certified with Bluetooth 4.0 onboard
https://www.bluetooth.org/tpg/EPL_Detail.cfm?ProductID=23788 Choose "view technical information" on the bottom right
https://www.bluetooth.org/tpg/EPL_Detail.cfm?ProductID=23788 Choose "view technical information" on the bottom right