The title pretty much says it. When Corner-type blocks (such as hull corner blocks) are replaced on the "Pick Remove/Replace filter" option by other Corner-type block (like, you are making a new painting/armoring on the ship/station) at the advanced build mode it does replace, but putting the block on the wrong angle then it previously was.
However, such problem only happens on the different angles that were introduced way later after the blocks were created, version 0.14 if I'm not mistaken.