I am missing log messages to indicate, which IP assigned to which MAC by coova 1.4. I remember these in older versions of coova to be present, to allow easy identification of clients device in question.
I.e. (on openwrt) I see
Mon May 6 06:08:58 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 3c:57:dd:c:bb:aa
...
Mon May 6 06:09:20 2019 daemon.info chilli[1331]: Successful UAM login from username=anon IP=10.1.0.2
So, device 3c:57:dd:c:bb:aa most likely is 10.1.0.2, but just guessing.
I am missing log messages to indicate, which IP assigned to which MAC by coova 1.4. I remember these in older versions of coova to be present, to allow easy identification of clients device in question. I.e. (on openwrt) I see Mon May 6 06:08:58 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 3c:57:dd:c:bb:aa ... Mon May 6 06:09:20 2019 daemon.info chilli[1331]: Successful UAM login from username=anon IP=10.1.0.2
So, device 3c:57:dd:c:bb:aa most likely is 10.1.0.2, but just guessing.