The cache is at the published coordinates, however, to claim a "Found It", you need to have completed the challenge. Otherwise you can log a "Write Note" until you qualify for the challenge.
To complete the challenge, you need to have:
Found at least 400 Unknown caches
Found at least 250 Multi caches
Found at least 25 Wherigo caches
Found at least 20 Earthcaches caches
Found at least 10 Letterbox Hybrid caches
Completed at least 80% of the D/T grid
Found caches on at least 250 days of the year
I have been thinking of this challenge for a while. As cachers, we aim for a lot of other side missions when we really get into caching. Aiming for things like D/T grid filling, 365/366 days caching, longest streaks etc, we do a lot of planning. So this one involves a few British series's, and a few other types of caches which people either avoid or don't know how to get started.
I play Grand Theft Auto, not as often now, but still do, and it is similar to caching in that away from the main aim of finding caches, we do these side missions to help us with our goal. Hence the challenge.
You can check your progress here:
Congratulations to JoeSmile on being FTF