I had the same experience recently, went to reverse and realized it was not available in the same place as it was before due to the new UI changes. Given how long ago this post was I am sure you’ve resolved this, but for anyone else who is searching to find the answer; This forum post: Quick Stack - reverse column order on mobile - #3 by Port_of_Folio
Give it s first or last in grid, or a stacking order. The quick reverse button is no longer available that I could find.