'Three suns rose together' in King Jie's 29th year: 1561 BC by the current text's own year count
Current text, Jie year 29: 商師取顧○三日竝出○費伯昌出奔商 (Shang took Gu; three suns rose together; Fei Chang fled to Shang). The text names each king's first year in the 60-year cycle: Jie 1 = renchen, Tang's year 18 (first as king) = guihai = 1558 BC, the text's date for the Shang founding. So Jie 1 = 1589 BC, year 10 = 1580 BC, year 29 = 1561 BC. Wang Guowei found the line in no older copy of the Annals: it matches the Han omen books ('when the Black Emperor fell, three suns shone together'; 'in Xia times two suns rose together') and the Bowuzhi story of Fei Chang seeing two suns before he went over to Shang, which is why it sits beside Fei Chang's flight.
How it connects
This clue from people supports this hunch
The 'three suns' of 1561 BC fall in the same year as the 2022 Thera candidate, but only by the current text's own year count, which was built centuries later the exact-year match
This clue from people is a clue for
Why did the Xia dynasty fall (about 1600 to 1530 BC), and do the omens told of its end remember a real eruption?
This clue from people we read it in
Wang Guowei, Jinben Zhushu Jinian shuzheng (where each line of the current text was taken from), juan 1, Chinese Wikisource