time-sensitive

adjective

physically changing as time passes
only relevant or applicable for a short period of time

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Examples from the Web for time-sensitive

Contemporary Examples of time-sensitive

This kind of attack is time-sensitive: it requires knowing precisely when and where a target is going to be.
NATO's Targeted Attack on Gaddafi's Son
Clive Irving
April 30, 2011