Octavian announced that he was giving up his power to the senate, but , in reality he kept all of his power and then the senate gave him a new name and it was Augustus witch mean ¨revered one¨ (17h 37min, dec 20, 27 y BC – 22h 29min, jan 16, 27 y BC)
Added to timeline:
Date:
17h 37min, dec 20, 27 y BC
22h 29min, jan 16, 27 y BC
~ 11 months