my fastest is 43 moves
Challange Mk2

Definitely much trickier than the knight puzzle, but fun to figure out! Not sure if this is optimal, but I got it in 22 moves:

[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "4k3/4p3/3pPp2/3P1P2/8/QQQQQQQQ/8/4K3 w - - 0 1"]
1. Qc7 Kf8 2. Qgf2 Ke8 3. Qea7 Kf8 4. Qab8+ Kg7 5. Qhf1 Kh6 6. Qaa8 Kg7 7. Qcd8
Kh7 8. Qda6 Kg7 9. Qac8 Kh7 10. Q3b5 Kg7 11. Qbe8 Kh6 12. Q3h3+ Kg5 13. Qhh8 Kg4
14. Qfh1 Kg5 15. Q1h7 Kg4 16. Qfh2 Kg5 17. Q2h6+ Kg4 18. Q6f8 Kg5 19. Q7g8+ *

I just realized that the puzzle from post #3 is different than the OP. I wonder how much the extra pawns influence the difficulty.

how do you put your game into a message?
go to learn then go all the way down and click on analysis click set up position copy the position from the puzzle then click load next click practice vs computer once you've finished click the download button download as a pgn then go to the place you want to post it and click insert chess game or diagram (its the first button) then click load from file , choose files, my files and it should say pgn and then a number then click insert here is an example
just like the last one but harder (POSTING MORE PUZZLES BELOW THREE A WEEK)
rules: get all of the queens to the back rank, don't checkmate, don't stalemate, DON'T TAKE ANY black pawns, and dont lose any of your own. try and do it in the least possible amount of moves!