Image Blocks Out of Order on Mobile View

When you add blocks to the page you are adding them to a grid. In this case, you've created three columns with four blocks in each, instead of adding three columns with two blocks, followed by three more columns with two blocks and so on. This is why they compress in the way that they do. 

You can resolve this by dragging the blocks around. It's easier to do by adding some line blocks to the page and then placing the blocks between them. You can remove the lines when finished. 

For example, here's a video showing four blocks that start out in the 'wrong' order on mobile. By rearranging them, they appear correctly.

See also the help guide: Moving blocks to customize layouts.