The success in identifying the middle two glyphs in the 236 long glyph sequence at the end of side b encourages us to look for the (single) middle glyph among the 25 at the beginning of side a:

Ga1-12	Ga1-13	Ga1-14

The glyphs once more agree with the numbers about where middle is.

236 + 25 = 261 implies there ought to be a single middle glyph also at number 262 / 2 = 131:

Gb5-12	Gb5-13	Gb5-14	Gb5-15	Gb5-16

The ordinal number is once again 13, but we are still not fluent enough in reading glyphs to either confirm or deny the proposition that Gb5-13 indicates the 'middle' of the 261 glyph long dark season.