Upend: Gravity Puzzle

You never touch a ball. You turn the world, and everything inside falls the way the new down tells it to.

That asks for a different kind of planning. A turn moves every loose thing at once, so the move that seats one ball usually disturbs another. Sockets grip what they catch, which is what lets progress hold: a ball that clicks into its cup stays there through every later turn.

Boards are built backwards from a solved one, so a winnable answer exists by construction rather than by luck, and the "best" figure is the true shortest turn count found by search.

No timer and no fail. Turn it as often as you like and watch where things settle.