As soon as requested (2,6)
I believe the answer is:
on demand
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">as soon as requested</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for on demand that I've seen before include "As soon as required" , "Whenever required" , "As soon as requested" , "When asked for" .)