I’ve noticed that there’s an area at the top of spaces that cards can’t be dragged into (they’ll stick at that border). However, boxes can be dragged beyond that border and when done repeatedly with a box that has cards in it, the cards get pushed down by the repulsion border which repositions them inside the box as the box itself moves.
Good catch. I’ve experienced a similar issue just dragging cards.
If you drag a card up to that point and let go, the card sometimes jumps above that point so placement at the top gets a little funky.
thanks for the report, will fix as soon as I can
released fixes for both the OP issue (boxes can be dragged to high), and for the card jumping issue reported by @kordumb