Which things in the manuscript can be dated?

[ReneZ]

we don't have a statement yet about the clothing in the Zodiac section by someone specialized in Medieval fashion

I know that I have not been very forthcoming on this, but there is this, from 2014:

Some initial comments from **, who has consulted some experts in his field. A medieval costumes expert (Roger Wieck from the Morgan Library) dates two of them to the 1420’s. This includes specifically the Virgo and Sagittarius illustrations in the Zodiac section. These costume styles would not have been largely known in the following decades / centuries, . . .