I have been thinking about this one and believe it would deal with a transition phase where the monarchy passes from Queen Regnant to King.
These former LiWs could well have had many tasks unfinished when the late Queen died. And people might still write to the Palace about the late Queen expecting some response about her.
And the Ladies could advise on ensuring that all tasks get to be covered by staff eventually one way or the other.
We will need to wait to see how far the LotHs remain into next year.