UV Layers

You can manage your UV maps in the CUt UV tool settings just to the right of the UV Editor toggle. In the UV Map popover, you can add or remove UV maps and set them as active for rendering, just like you would in the Object Data tab of the Properties Editor.

If Seams Per UV Map is enabled in the add-on preferences, UV Flow will store a different set of seams for every UV Map as if it was a seam layer, so that you can easily work with multiple maps at the same time. The seams are stored in the object data attributes and are automatically saved any time the active UV map is switched, so you can modify them even when not using the tool.