This style of dress saw very little change from about 1500 through the 1520s. The thing that makes it lean 1520 versus 1505 is the trim. Raphael’s 1505-1507 Florentine portraiture shows a single line of trim. “The Preaching of St John the Baptist” shows the patrons in similar dresses (with two sleeve variations) with two lines of trim near the neck.
This was the second dress I sewed.