Mamari period no.	1	2	3	4	5	6	7	8
number of nights	2	6	3	4	5	3	5	2

Keiti period no.	1	2	3	4	5	6	7	8	9
number of nights	1	1	6	3	3	5	3	5	2

I have here counted 'staffs' (with special treatment of periods nos. 3 and 6). Evidently we can reduce the number of periods in Keiti to 8 if we add together periods nos. 1 and 2. Then we will have:

There is one night missing in Keiti's period no. 5 (called no. 4 above). Does this mean that we have 29 nights in Keiti instead of 30 nights as in Mamari? We still don't know which of the nights in Mamari should be skipped each other month, but considering the results above I would guess that it is this strange glyph in period no. 4: