What was up with ‘part 2’?

Overall I enjoyed the book …. the first part of the book. I don’t know why part 2 was added and honestly it didn’t work for me. Halfway into the ‘second’ part, which focuses more on Hilma, I wanted to stop. We weren’t world building anymore. The senso angle dropped. We flash forwarded WAY too far. Felt like it had nothing to do with the Hallowmas train. Throw in a side of nuns and a mini murder mystery?

It was odd and didn’t fit. Ruined the whole book for me.