because it's all relative. when i say large swathes are undefended, i mean locally as the ukrainian military maneuvers its troops all around the front while trying to create an illusion of solid defense. the primary event i'm speaking of is the rapid advance to the north or shakterskoe and around velikaya novoselovka. when it started deepstate said something like: "further enemy focus on the region is now guaranteed since they are now aware of the situation and have seen everything" (referring to empty trenches). and even if trenches are unmanned, lighting fast advance is also complicated by minefields, same issue that ukraine had during the 2023 offensive. as for the other regions, it's probably because the government wants to focus on taking everything it already formally annexed and possibly also reach the dneprooetrovsk region, which is one of the main candidates for further annexation.
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