Gambit Boundary Layer
 

I have a basic doubt, can i create a new boundary layer in gambit after i have actually meshed the model. Say i have a flow through a pipe and i have already meshed the annulus region using volume mesh. Now i realize i need to refine the mesh near the wall of the annulus to get better flow information, can i create a new boundary layer now? after premeshing is it possible to create new BL?