What's the meaning of "Set due date uses the deck's configured starting ease"

Anki Desktop
1

In the Scheduling changes of Changes in 2.1.45, :

I can’t understand “Set due date uses the deck’s configured starting ease”, I need help :joy:

2

I set due date for a card ,but its ease has not changed to deck’s starting ease.Is something wrong?

3

The ease is only changed when used on a new card.

4

thanks