Beyond the 'Sun' day at the end of line a7 the beginning of the following (upside down of course) line a8 is quite interesting. First comes a repetition of the end of line a7:

Ea7-34	Ea7-35
Ea7-36	Ea7-37	Ea7-38	Ea7-39 (256)
Ea8-1	Ea8-2	Ea8-3	Ea8-4 (260)	*Ea8-5	*Ea8-6
*Ea8-7	*Ea8-8

Then follows 4 only partially visible glyphs (as if the light source has begun to sink below the horizon in the west). In their center (between Ea8-4 and *Ea8-5) there is a wormhole in the tablet, which motivates my asterisks at the following glyph labels in line a8.

This wormhole has a significant location - it is immediately beyond glyph number 260. Counting time, though, means day number 260 is a zero day. Light disappears already during the 259th day (Ea8-3).

Anyhow, Sun seems to be crawling down through this wormhole at the end of his 'daytime' journey. He goes into limbo.