The 10 o'clock pushbutton on the Langematik Perpetual Calendar -- which is recessed on all the later versions but is large, rectangular, and protruding on the yellow gold and earliest platinum models -- advances all calendar functions by 1 full day with a...
It is a practical thing that makes setting very easy. Regarding my Zeitwerk post: I think, I should also read it again, as the exact details are hard to keep in mind ...