The need to use software instead of hardware for beacon timers in AP+STA mode (aka nosbeacon) is now just determined in software, as we always knew whether or not to enable this.
The confusing bssid and -bssid parameters are now deprecated.
The "uniquebssid" flag is equivalent to "bssid" and can be used to force IEEE80211_CLONE_BSSID flag. If this is not specified, then the BSSID used will be the next unused BSSID in the sequence, which could very well be the parent device's MAC address.
"uniquebssid" equates directly to IEEE80211_CLONE_BSSID" flag therefore.