The new rules for prone state (page 165 in the pdf) says the following: ► A Trooper may change its status from Normal to Prone, and vice versa, at either the start of their Movement or at the end of their Movement, by performing any Short Skill or ARO with the Movement label (except for Jump) or as a result of a failed Guts Roll. However, this will affect their Silhouette and the distance they can move around the game table . So as I read it a model that is not prone, with 4-4 movement, can declare a move, walk 4" and go prone. Then declare a second move, stay prone and crawl 2", then stand up. A game example would be a specialist moving to an objective and dropping prone behind it and using their second skill to push the button. Is this correct? Pretty big change, but it makes sense :)