One strong point for this model is that the calendar has two months before sun arrives, which is in agreement with how I have interpreted a Maya calendar:

5 Tzek	6 Xul	7 Yaxkin	8 Mol
9 Ch'en	10 Yax	11 Sac	12 Ceh
		200
13 Mac	14 Kankin		15 Moan
16 Pax	17 Kayab	18 Cumhu	19 Vayeb
1 Pop	2 Uo	3 Zip	4 Zotz

20 days in each month means sun is 'barred' during 60 days (Pop, Uo, and Zip), and the open mouth in Zotz illustrates how light is returning (left means future here).

Moreover, this idea of a period of 60 days in waiting beyond winter solstice has ancient roots also in our own classical time.