"At what time?" (4)
I believe the answer is:
when
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">at what time?</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for when that I've seen before include "As soon as" , "At what time?" , "stop pouring the drink" , "Say it when you''ve had enough" , "Over what period?" .)