MQTT sensor set by Blue Iris - losing entries from logbook

Configuration
1

I’ve finally decided to integrate my Blue Iris NVR into Home Assistant. I activated the MQTT add-in and integration, and set Blue Iris to post “motion” and “no motion” payloads for a couple of cameras, and MQTT sensors to capture them. I set-up a logbook card to watch for them, and sure enough they were appearing when expected.

The strange thing is though, after seeing a “changed to motion” entry appear in my logbook, and then a “changed to no motion” appear after the reset from BI, the original “changed to motion” entry disappears. Can anyone help me understand how that might happen?

Notice there is a “changed to motion” at 12:46 here:

2290fda3b5996f8897944cc01426bd6f02a0fe6f (1)
2290fda3b5996f8897944cc01426bd6f02a0fe6f (1)750×577 67 KB

…and then it has gone shortly afterwards:

82D73649-378F-42C9-9698-E07AC4E8CED0
82D73649-378F-42C9-9698-E07AC4E8CED0747×461 50.5 KB

The status change can still be seen here though:

image
image750×527 67.4 KB

The sensor is simply:

  - platform: mqtt
    name: "Blue Iris alerts - rear"
    state_topic: "BI/rear"
2

I have this working as expected now, by using binary sensors instead, as per Blue Iris Integration Tutorial.

Still not sure why my config was causing entries to disappear though…