1handful,
Julie did a great job of answering your question, so I'll just pop-in to agree.

After RTR, we have two guides left in the history cycle (before the geography guide which comes after that). Pilgrim's Progress will be in one of the last two guides in the history cycle. The other guide will have a worldview resource scheduled for parents to go through with their kiddos. Right now, we aren't sure which one will be in which guide, as it will depend on how difficult the worldview material is (and we are still deciding between a couple of excellent choice for that).
I hope that helps!
Blessings,
Carrie