[No Spoilers] Soapstone issues post final boss.

I just beat the game, and opted to not go directly into NG+ in order to have some fun helping some friends out with later bosses. However, my soapstone doesn't seem to be working anywhere at all, as in, it is grayed out and I am unable to use it anywhere. Is this normal? Is the White Soapstone disabled after you beat the final boss?

EDIT: Alright, I spent some time testing. It seems that at my current level (86) with a +10Sword, and having beat the game. I am unable to put my sign down ANYWHERE prior to The Catacombs as it relates to bonfire placement on teleport selection.