Ambush - Quickly chase after the army that attacked us to recapture half of the land they stole from us. Unsuccessful strikes, attacks that used anonymity or war spoils, and all attacks by Avians may not be ambushed. We have only until our enemies’ armies return to their own lands with their spoils to ambush their attacks, or the opportunity is lost to us forever. Further, we can only attempt to ambush each successful land attack against us once – if we fail, we are unable to ambush that attack.
This still says that Avians are immune to Ambush. I know most of us probably never look at the Guide, but a guy in my kingdom that just came back after the first time in a few years pointed it out to me today, so we should probably fix it for other return players, so they don't get confused.