When using a block swapping technique to change a magma block water column to a soul sand water column, the bubbles generated take way too long to propagate up the column. This results in jerky bouncing up the column after swapping the bottom block to soul sand and keeps you going up long after the block has swapped back to magma.

This effect is not present in the Java edition.

The image attached hopefully clarifies what I mean with the block swapping.