The cache IS at the posted coordinates.
In order to LOG this challenge cache, you must have attended a CITO Event every month of the year. This means you have attended at least 12 CITO (Cache In Trash Out) Events, one in each month. You may sign this cache and write a note at anytime, but can only log a find once you qualify. The CITO's don't have to be consecutive. Any month in any year counts.
Fortunately, there is a usually a CITO event hosted by a SoCal Geocacher almost every month at The Seal Beach Save our Beach event. Check it out and look for a geocaching event to be hosted most months.
Also, keep in mind, anyone can host a CITO at any time and any place, it doesn't have to be organized by an outside organization, it's just nice to know that one exsists. Help spread the word of geocaching in your area, by hosting Cache In Trash Out event. Host a clean up in your area and others will come.
Cache In Trash Out® (CITO) is an environmental initiative supported by the geocaching community. Since 2002, CITO has helped preserve the natural beauty of cache-friendly spaces. In that time, more than 363,000 people have volunteered at over 29,000 events.

Congratulations to SoCalGirls for the FTF. We watched it all week and wondered if she would make it there for the FTF.