A change to the law of royal succession has been enacted by some of the 16 Commonwealth Realms, to become effective when all of them have done so. Its most conspicuous feature is removing the preference for male heirs, but only from those sons born after 28 October 2011 (the date of the conference where the terms were decided).

Rather than the date cutoff, it would be simpler in my humble opinion to make explicit exceptions for past cases where sex trumped seniority. There are only two since the last change (1702) in succession law; thus: The descendants of King George III shall precede those of his elder sister Augusta, Duchess of Brunswick; and the descendants of King Edward VII shall precede those of his elder sister Victoria, German Empress.

Augusta’s heir by sex-neutral primogeniture appears to be Prince Alexander of Wied, born 1960, unless her first great-granddaughter Marie of Württemberg (1807–1865), countess of Neipperg, had issue not mentioned in Wikipedia.
Victoria(jr)’s heir by the same rule is Dr Friederike von der Osten, born 1959.

This curve-fitting thingy is one of several projects on which I’ve made progress in rare fits over several years. It ran into two big snags. I haven’t found how to determine which gridpoints are within the pen-width of a blending arc; two methods that ought to work don’t. (What would help: tutoring in drawing pictures in a MacOS display, so that I might have a better idea where they go wrong. And a pony.)

The other snag is this: For each pair of arcs, there is an infinite family of blending arcs; how to choose the osculation points to minimize rapid changes in curvature, while meeting the gridpoint constraints? ( . . more . . )