<p>Expired bounties are awarded hourly. In addition, we wait for another hour after the grace period has ended (just to make sure that e.g. rounded time values don't cause a user to be two minutes too late). Note that this is just the documentation of <em>current</em> behavior; obviously don't rely on this.</p>

<p>Summing up these two, there <em>may</em> thus be a delay of up to two hours between the end of the grace period and the auto-awarding.</p>

<p>The <a href="https://stats.meta.stackexchange.com/questions/1185/is-this-a-bug-or-is-there-a-large-lag-between-the-time-the-grace-period-ends-and/1193#1193">16 hour delay</a> that happened in this very case is not supposed to happen; it was due to the fact that the service responsible for scheduled tasks (like auto-awarding bounties) <a href="https://meta.stackexchange.com/questions/134743/very-unusual-number-of-users-logged-into-the-chat/134749#134749">was down for while</a>. The bounty was awarded as soon as I had brought that service back online (if you compare the time stamps, you'll notice that I posted my answer on Meta.SO shortly after the bounty was awarded).</p>
