However, E1 is usually preferred over E2-extended because of the more convenient scheduling. On E2-extended, the total sleep is high, which often causes high sleep onset for all sleeps. Similar to E1, naps often take a long time to learn. So far, there has been one successful case in which the first nap scheduled only 2h after the 6h core (a high sleep requirement individual). This makes the variant easier to schedule, but can be difficult or impossible to fall asleep only 2 hours after a long core.
