PDF Bookmarks out of order for multiple flow document
This is the first time I've tried to work with multiple flows, so it's entirely possible I've missed something obvious.
Pertinent information:
Windows 10 Pro (Build 1909, OS Build 18363.1316) (Yes, I know it's a few releases behind, but updating from here bolluxed my Acrobat DC Pro beyond belief)
FrameMaker 2020 (16.0.1.817)
Acrobat DC Pro (2021.001.20138)
This is my current setup for the first page of our new Field Bulletin template. The letters indicate the Flow Tags. Flows A and B are disconnected because they appear only on the first page and because I do not want the information in them to flow into the other frames. Flow C is the main flow.

As you can see, I have the book title (it's a variable) in Flow A, and it is tagged with H1 Heading 1. I have the text "Technical Support" in Flow C, and it is tagged as H2 Heading 2. When I generate the PDF, this is how the bookmarks are set up

But this is what I want them to look like (obviously):

I've tried to set the PDF to generate both by Articles: Thread by Text Frame (hoping it would follow the Flow labels) and also Articles: Thread by Column, which was the recommendation I found here.

Both choices resulted in having the heading tag for the book title appear after the heading tag for the Technical Support.
What am I doing wrong? Yes, I know it's an easy fix in Acrobat DC Pro, but it shouldn't need to be fixed.
Side note: Originally, Flow C was Flow A, Flow A was Flow B, and Flow B was Flow C. I renamed them because I thought that might be why the bookmarks weren't coming out in order (that is, Acrobat was moving from A to B to C), and since Technical Support was in Flow A (at the time), it was being processed first. Alas, changing the flow tags didn't change the PDF results. Also, weirdly, they are showing at the same hierarchy level in the PDF bookmarks pane, despite being setup to indent in FrameMaker.



