Dynamic Lightings Walls for a Multi-layer Map

I have recently implemented Dynamic Lighting in my campaign, so I'm pretty new to it. One trick that I used to used prior to DL was to put the "second floor" (or additional levels/layers) of a map on the GM Layer and shift them to the Map layer when the players discovered that part. The issues that I'm having is that if I set up DL walls for the first floor and the layout of the second floor isn't the same, the DL walls are useless. Is there a way to hot-swap wall sections to and from the DL layer? In most cases, my additional levels are split up into single rooms (so that I can reveal them one at a time), and I don't want to make a separate map for one room. 

The way I've done this is to have all the map layers on the same map page, with DL barriers between them, running the length or breadth of the page (or in boxes, if the areas are small enough, like a tower).  The GM then moves the characters to the new area when they reach it (since all the characters need to be on the same map page).  The other (messier and ultimately impractical) option would be to keep the new DL "walls" in a remote location on the GM layer and then move them onto the existing area after you've moved the floorplan.  I leave the problem of getting rid of the previous DL walls as an exercise for the alert student, as well as that of aligning the new DL "walls" with the accurately-placed floorplan.