Ideas:

1. Already with the first glyph in the week according to Large St Petersburg we can observe that neither the glyphs nor the number of them are identical with those of Large Santiago. This is not something to regret, but on the contrary will give us opportunities.

2. In Large St Petersburg Sunday and Saturday have "knives" (according to Clara) which are different from those of the rest of the week. Those of Sunday and Saturday are more bent and sturdy. I guess this means that both Sunday and Saturday have a higher status, that they are 'kings' so to say, with more power than the rest of the 'planets'. The powers at the start and at the end of the week are in this way being balanced.