Translations:DC2/17/en
From Polyphasic Sleep Wiki
Extended

The second core can be extended to a 3h sleep. People with high sleep requirements (especially in both REM sleep and SWS) may benefit from the extra sleep. The first core can also be delayed, starting possibly at midnight. However, DC2-extended has seen very few attempts, and virtually no success. DC1-extended and E2-extended are recommended instead, as both are easier to schedule, and likely no more difficult to adapt to.