Ok, Joshua is all over this one. The default wait time between searches is 15 seconds, but one of our servers has evidently decided it would prefer to work on a slightly different clock

So what happens is, the initial search is performed on server A, say, at 10:00. The second search happens to be performed on server B. Let's say Server B is running 10 seconds behind Server A ... six seconds have gone by since the initial search, so Server B thinks it is now 9:56. Server B checks the recorded time of the initial search (as recorded by Server A), sees that it was 10:00, adds 15 seconds to that and compares it to its own current time ... and spits out the seemingly ludicrous statement you posted above

Hope that makes sense. Probably more info than you wanted.

Joshua is working on resetting the server times as I type this to get them all working on the same clock again.