This is strange. I'm going through this book making good pages. I lost a page at the end of a chapter and deleted it, which moved the chapter opening page back one. Now, from there on all the running heads on the text pages are off. I have to apply the master page spread again from there to the end of the file. If I delete another page, I have to go through the whole thing again. I'm not using Liquid Layout, but I do Enable Layout Adjustment (as I always do).
Here are some screenshots:
1. How the spread should look with the running heads positioned properly.
2. How the spread looks if I delete a page before it.
3. The dialogue box that appears when I choose to reapply the master pages.
I'm at a loss. This has never happened in any previous version of InDesign.