Might be that I’ll add to this. I think I found other odd things that I’ve already forgotten!
If 47 puts the newspapers in the letterboxes, the jogger starts to pick them up. She stopped at four I think (given the achievement is to put five in) - anyone seen anything further? What does she do?
In the Janus basement there are four busts on plinths. One of the two black plinths is higher than the other three. Picking up a bust raises the plinth; without trying all combinations it looks like the first two that are picked up raise those two. What does this do? Actually, without trying, I managed to get the three that were lower all raised at the same time. Does anyone know what this is about? Edit already, it looks like the other two black and white plinths, the two by the place where the Ark picture is, are involved, I got to a point where the two black ones were raised and the two white lower, I then put the two black on the black one (by the picture) and the two white on the white and then the plinths where the white ones were originally were higher. What is going on?!