Check if the interfaces are in the interface list, that you have allowed discovery on.
And 12 points goes to
normis!
Discovery was allowed only on the LAN and ether1 was part of WAN. After allowing discovery on all interfaces, everything started working as expected. Thank you very much.
@ivicask, removing firewall rules restored the ability to access via IP. Before that, only way to configure was over WiFi.
I think the reason for those FW rules being there is to prevent a situation where someone (unknowingly) connects wAP's ethernet straight to WAN.
Btw, is it something that has been changed in recent ROS versions? A while back I was installing some cAP's (the original ones) and I remember clearly that I was able to configure them over the cable in their default config. Or is the cAP's def. config different from wAP's?