It only applies to the descendants of Charles
It doesnít just apply to the descendants of Charles, it applies to all born after 28 October 2011.
Iím just curious why it didnít apply to those born the time?
Anne would be above Andrew and his daughters that way - Iím wondering if because Andrew is Elizabethís favourite that idea was not allowed?
Succession changes are only rarely applied to the established adult line. The only one that I know of was Belgium in 1991...before the change the line was 1. Albert, 2. Philippe (b. 1960), and 3. Laurent (b. 1963). With such a short line and changing it from agnatic primogeniture to absolute primogeniture it made sense to adjust the full line...1. Albert, 2. Philippe (b. 1960), 3. Astrid (b. 1962), 4. Amedeo (b. 1986), 5. Maria Astrid (b. 1988), 6. Laurent (b. 1963).
In Sweden, Victoria was 2.5 years and CP was 7.5 months when they switched from agnatic primogeniture to absolute primogeniture so switching the kids made complete sense...and before the change the line was only 2 people long (post change 3 people).
Looking at other European monarchies...Denmark change from male-preference to absolute primogeniture in 2008 had no effect on the line at the time. Luxembourg's changes for agnatic primogeniture to absolute primogeniture in 2011 is only for Grand Duke's Henri's descendants...so at the time only added Alexandra in before Sebastian. The Netherlands went from male-preference to absolute primogeniture in 1983 but I don't think it affected anyone at the time.
Norway did like the UK in 1991...kept Haakon (b. 1973) before Martha Louise (b. 1971) and just changed the line for their descendants.
Spain and Monaco are still male-preference and Liechtenstein is still agnatic primogeniture.