Things must be slow I cant believe we have found 12 different things to say about a simple question.
I can understand the reason for the question but shirley it is common sense -
go around - we all know what that means,
not below - dont go below the specified height.
Simples
Another circumstance you will hear something simillar is join left base (or whatever) not below x feet. So join but dont descend below the specified height as there may be someone else there.
Restrictions like this are simply to stop you running into to someone below.
It really has got to be that simple hasnt it!
(Edited to add: yeah it is a bit slow today and really just wanted to join in with everyone else by thinking of something else to say!!)