User blog comment:Xilinoc/Ch. 686 - Death & Strawberry (End of Bleach reMIX)/@comment-2243814-20160818182335/@comment-24053170-20160819183240

Actually they sort of made a barely noticeable reference to the royal guard, namely Oetsu. Remember that Oetsu makes the Asauchi for all soul reapers regardless of who they are.

And we see at the end of the final chapter that Ichika has a Zanpakuto of her own, meaning that Oetsu had to have survived in order for new ones to even be made.

Basically thats all were going to get about the royal guard. Take it or leave it....