Tube station has 86 steps down but only 48 steps up
 

My last post was wrong. The bottom sign is 20 steps above the platform.

There are three groups of steps: 18, 48 and 20. As Helen says, the lift
bypasses the top 66.

I still do not understand why the warning signs are the way they are.
Perhaps they used two different sign contractors. Or maybe it is a joke
in tribute to Willie Rushton (there is a plaque to him at the top of
the stairs too).