Question about Christmas event (spoilers)

1)Why Ishtar don't have any role in this event?
I played every event after accel zero and each event have banner that have servant who have their role in each event. But this is not for Ishtar. I don't see her even after completed story mode.

2)Did there have some changes in event rerun?
I saw Ceasar refer to Cleo that she don't play with him in Christmas rerun. But at that time this event released, Cleo is not already released. Did creator change some text for new players