[Jason.]

I've always wondered what they do in hiding.

I remember Tamara from BB15 saying on Couch Potato that they went into hiding on the 28th May 2014, which is about a week before the series started.
Though, I'm not sure if they all go in at the same time.

I've always thought they spend the time doing VT's and photos as well as interviews.

I also wonder how the housemates get to the eye before they enter.

Do the housemates leave at separate times or does a car go and get them one by one and plant them there.

If you notice before Emma reveals a housemate, the hole in the pupil of the eye, where it closes is black with lights, meaning nobody is standing behind it, as it's the background.

Little things like this are interesting.