All hardware is brand new, 1 x SG125 and 1 x AP50...
During provisioning of a AP50, the logs shows this during "boot":
2014:12:19-07:45:03 10.210.15.203 netifd: lan (846): Performing a DHCP renew
2014:12:19-07:45:03 10.210.15.203 netifd: lan (846): Lease of 10.210.15.203 obtained, lease time 85207
2014:12:19-07:45:04 10.210.15.203 kernel: [130368.470000] device wlan0 entered promiscuous mode
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Configuration file: /var/run/hostapd-phy0.conf
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: TDLS supported
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: TDLS external setup
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Supported cipher 00-0f-ac:1
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Supported cipher 00-0f-ac:5
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Supported cipher 00-0f-ac:2
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Supported cipher 00-0f-ac:4
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Supported cipher 00-0f-ac:6
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Using driver-based off-channel TX
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Use separate P2P group interface (driver advertised support)
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: interface wlan0 in phy phy0
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: 2402-2482 @ 40 MHz 20 mBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: 5170-5250 @ 80 MHz 20 mBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: 5250-5330 @ 80 MHz 20 mBm (DFS)
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: 5490-5710 @ 80 MHz 27 mBm (DFS)
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: 57240-65880 @ 2160 MHz 40 mBm (no outdoor)
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Added 802.11b mode based on 802.11g information
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=1 freq=2412 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=2 freq=2417 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=3 freq=2422 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=4 freq=2427 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=5 freq=2432 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=6 freq=2437 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=7 freq=2442 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=8 freq=2447 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=9 freq=2452 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=10 freq=2457 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=11 freq=2462 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=12 freq=2467 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=1 chan=13 freq=2472 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Channel 14 (2484)is disabled!!
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=1 freq=2412 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=2 freq=2417 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=3 freq=2422 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=4 freq=2427 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=5 freq=2432 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=6 freq=2437 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=7 freq=2442 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=8 freq=2447 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=9 freq=2452 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=10 freq=2457 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=11 freq=2462 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=12 freq=2467 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Allowed channel: mode=0 chan=13 freq=2472 MHz max_tx_power=20 dBm
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Channel 14 (2484)is disabled!!
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): ACS: Automatic channel selection started, this may take a bit
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): ACS: skipping channel 14 (2484)
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): ACS: Scanning 1 / 5
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): wlan0: nl80211: scan request
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2412 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2417 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2422 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2427 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2432 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2437 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2442 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2447 MHz
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): nl80211: Scan frequency 2452ifconfig: SIOCGIFFLAGS: No such device
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Interface 1 setup failed: IFUP_ERROR
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): ifconfig: SIOCGIFFLAGS: No such device
2014:12:19-07:45:04 10.210.15.203 netifd: radio0 (22729): Interface 2 setup failed: IFUP_ERROR
2014:12:19-07:45:05 10.210.15.203 netifd: lan (846): Performing a DHCP renew
2014:12:19-07:45:05 10.210.15.203 netifd: lan (846): Sending renew...
2014:12:19-07:45:05 10.210.15.203 netifd: lan (846): Lease of 10.210.15.203 obtained, lease time 85206
2014:12:19-07:45:12 10.210.15.203 kernel: [130376.140000] br-lan: port 2(wlan0) entered forwarding state
2014:12:19-07:45:12 10.210.15.203 kernel: [130376.140000] br-lan: port 2(wlan0) entered forwarding state
2014:12:19-07:45:12 10.210.15.203 netifd: Network device 'wlan0' link is up
2014:12:19-07:45:12 10.210.15.203 kernel: [130376.170000] device wlan1 entered promiscuous mode
2014:12:19-07:45:12 10.210.15.203 kernel: [130376.180000] br-lan: port 3(wlan1) entered forwarding state
2014:12:19-07:45:12 10.210.15.203 kernel: [130376.180000] br-lan: port 3(wlan1) entered forwarding state
2014:12:19-07:45:13 10.210.15.203 kernel: [130376.600000] device wlan2 entered promiscuous mode
2014:12:19-07:45:13 10.210.15.203 kernel: [130376.610000] br-vxlan102: port 2(wlan2) entered forwarding state
2014:12:19-07:45:13 10.210.15.203 kernel: [130376.610000] br-vxlan102: port 2(wlan2) entered forwarding state
2014:12:19-07:45:14 10.210.15.203 kernel: [130378.140000] br-lan: port 2(wlan0) entered forwarding state
2014:12:19-07:45:14 10.210.15.203 kernel: [130378.180000] br-lan: port 3(wlan1) entered forwarding state
2014:12:19-07:45:15 10.210.15.203 kernel: [130378.610000] br-vxlan102: port 2(wlan2) entered forwarding state
Why the IF_Up errors??
Looks like the ACS never completes?