I don't know, but it's been there for a while now. Each evening as I walk down to the tube the pink glow catches my eye and I smile.
Of course all art has a message, and that message is different for each viewer because of what we bring with us. Myself, after an initial smile, I found I was taking the caption of the work quite literally to heart. Like many people I read the newspapers and probably grumble if I see something about a freedom which seems to be curtailed in some way. Negative. So what is the positive? What am I not doing that I'm free to do? Plenty, the more I think about it the more I think I should get out and do stuff! Things I've always wanted to do but thought I couldn't. Actually there is nobody but me stopping me doing pretty much anything I want. Yeah!