Very recently we have decided to time runs in IGT along with RTA. The reason we have decided to do this is because of how unreliable the load times and time in orbit is. I have posted in the resources page of the site a time calculator that will help you time the IGT of the runs. IGT will be timed by adding all of the mission times together which is in the same rules as if you were timing IL times. For runs like the All Story Ultras run you go to orbit once you kill the ultras you need to in the level and check what your IGT was in the mission report. We still recommend that you also time the run in RTA as well so you can have a time with loads and orbit.

I hope this clears up any questions that you have with the new timing rules.