I noticed that once i formed a ceasefire agreement with an AI player, the game still treated them as an enemy for noticications.
they were flagged as hostile, left a hostiles message when jumping to and entering my systems, and they even whispered the insulting message when they entered my systems
the problem persisted even when I made a peace treaty and had a relationship of 120%
they behaved as though allied where ships abilities, trade routes, and autoattack were concerned. it just seemed like the UI was treating them differently