It's complete pot luck mate. I set 3 trackables in the same cache at the same time. One was logged out and hasn't been logged since, on was removed without being logged and is now lost, and the last one has been properly logged and is currently making its was aound Surrey.

As said, a Premium Member cache would be the best place to start it, but then it's who picks it up once it lands in it's first normal cache.

I tend to move trackables to events, series bonus caches or puzzle caches as people who go to them tend to care a bit more. But again, it still doesn't stop it from being moved to any cache afterwards.