How does deck determine which cards without due dates show up on "Upcoming Cards"?

Title says it all. In the new “Upcoming Cards” overview (super nice feature btw) there is a list for cards without a due date (no due). For me, it only shows some, not all, of my cards without dates. How does deck determine what goes into that “No Due” list?

It does not work for me as well.
I created card with no due date ant it is not on the “No due” list.

Nextcloud 19.0.3
Deck 1.1.0

I eventually figured it out. As far as I can tell, when the card is assigned to the user without a date, it’ll end up in the “Upcoming cards” list…

@aproposnix since we (as Deck Android developers) had the same issues finding out how this mechanics works in the Deck server app, i wrote a little tool which helps you to explain why a cards is or is not visible on the Upcoming Cards view:

Please consider it as a documentation of the current state and post change requests about the mechanism exclusively in the Deck server app repository (the Deck Android app will follow when something changes)