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