How does ID xp work?
A (non-Master) ID gains experience by making a change to your character, giving you a holo-emote(s), or migrating your stats. The amount of xp is based on how long the timer is. The exp does not stack, so it would be kind to suggest an ID break up a long session into a few parts (accepting whatever has been done so far when the timer hits zero) so that they can get exp for more than one change.