Hold mode is immediately disabled on that axis as soon as you move the stick away from center on the iGyro and reengages only when the stick is re-centered.

I'm not sure how to describe why, but flying a fixed wing around in hold mode on the Cortex, other than to do torque rolls, is a bad idea. Trust me I have a lot of experience with gyros, several of my articles are on manufacturers web pages for how-to info.