Ttn-mapper differences between (public) heatmap and advanced maps?

Hello, I have noticed that most of my positions recorded by my tracker are displayed in the advanced maps but not in the heatmap. See screenshots. Is this a bug or a feature? If it is a feature, where can I read about it.

  1. heatmap
    tnmapper_heatmap_köt_public

  2. advanced maps

You may want to read the thread about TTN Mapper on the main list of topics about its downtime.

Particularly as I’m about to put some news on there.