Vintage Persian Flatweave Kilim Accent Rug

The lateral of the three panels shows narrow and relatively even dark brown and beige weft stripes, but they flank a much wider central section with wider convex or drooping narrow bands. It is presumed that they were originally part of the same long band, but is it all the work of one weaver? Changing weavers, changing work, or just a change in materials and imagination?  NW Persian work with dyed yellow, blue, and teal lines among most of the undyed brown and beige wool. Backed.