Oh my god, I am german spoken and this is hard to understand in english.
The DeepL transator, (which is usually very good) makes it completely confused.

I hope this translates to this semantically:
1) A sequence point is a finalizing point where all preceding calculations and initializations are completely processed.
2) An initializer list is strictly evaluated from left to right, and each bracketed initializer term ends with a sequencing point.

I hope I am not in error ; (I hope and assume this, because it makes some sense for me)

a = {
  .b = 1,
  .c = 2,
  .d = 3
};

a = {
  .b = 1,
  .c = 2,
  .d = a.b
};