It do check for updates and invoke the patcher if there is a pending update. Otherwise it'll skip the Conan patcher by default. You can, should you want to, hold shift+F8 before you start the game, it'll force the patcher to appear, for reading news, change settings, do database integrity check or restore corrupted parts of the default UI. While alt+F8 skips the check for updates, forcing the game to start should you get caught in an infinite update loop. And ctrl+F8 will bring up the aoc.exe configuration.
No documentation yet, it is still a pre release.