Drastic reorganization (5-2)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">drastic reorganization</span>' is the definition.<br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for shake-up that I've seen before include "Big change" , "Fundamental change" , "Disturbance: reorganisation" , "Major reorganisation" , "Drastic reorganisation" .)