Affinity Publisher version: 1.9.1
Mac OS version: 10.13.6
Reproducible: Always (see attachment sample file)
It seems to me that Bleed Hazard Preflight Check is unable to detect objects adjacent to the bleed area if these objects are placed inside a Master Page. In my case I created a Master Page with a dark background. I used a rectangle to draw this background and I didn't realize that it was adjacent to the bottom bleed. Needless to say, I can see the cut line in the printed photo album. I believe this should not work this way.
In the attached sample file, you can see that only the blue rectangle (in Page 1) rises a hazard. The red rectangle, instead, is pretty fine with the check but is going to be cut when printing
Thank you,
Andrea
Untitled.afpub