ERPoe-5 + UniFi AP port speed issues

Hi there.

My network looks like this: internet (about 70-80Mps both sides) comes to eth0 port, unifi ap wired to eth1 port (poe 24v). 

Out-of-the-box Unifi AP said that it's "connected" in UniFi controller. After upgrading to latest firmware UniFi controller said that it's "Connected 10FDX". Hmmmm I thought and tried to downgrade UniFi firmware with no success with that port speed, it show "Connected 10FDX" after firmware downgrade. 

Then, entering ER config section, I've maually changed port speed from "Auto negotiation" to "100 full". Looked like solution, but UniFi controller shows "connected 100HDX" (instead of 100FDX)
.
So, the questions is: whom is to trust? To UniFi controller whith its 100 half-duplex or to ER with its 100 full-duplex port speed?

Thanks for help!