diff --git a/src/libANGLE/renderer/vulkan/TextureVk.cpp b/src/libANGLE/renderer/vulkan/TextureVk.cpp
index 130abe1f6f..4b13553ed4 100644
--- a/src/libANGLE/renderer/vulkan/TextureVk.cpp
+++ b/src/libANGLE/renderer/vulkan/TextureVk.cpp
@@ -3921,6 +3921,15 @@ angle::Result TextureVk::initializeContents(const gl::Context *context,
                                             GLenum binding,
                                             const gl::ImageIndex &imageIndex)
 {
+    // POC INSTRUMENTATION: log every robust-resource-init clear so we can show
+    // it is NOT invoked for the dropped cube faces.
+    if (mState.getType() == gl::TextureType::CubeMap)
+    {
+        fprintf(stderr,
+                "[POC-ROBUST] robust-init clear for CubeMap level=%d layer=%d\n",
+                imageIndex.getLevelIndex(),
+                imageIndex.hasLayer() ? imageIndex.getLayerIndex() : -1);
+    }
     ContextVk *contextVk      = vk::GetImpl(context);
     const gl::ImageDesc &desc = mState.getImageDesc(imageIndex);
     const vk::Format &format =
diff --git a/src/libANGLE/renderer/vulkan/vk_helpers.cpp b/src/libANGLE/renderer/vulkan/vk_helpers.cpp
index 1429619383..8c4d3f164d 100644
--- a/src/libANGLE/renderer/vulkan/vk_helpers.cpp
+++ b/src/libANGLE/renderer/vulkan/vk_helpers.cpp
@@ -9820,6 +9820,24 @@ void ImageHelper::stageSelfAsSubresourceUpdates(
 
     if ((~skipLevelsAllFaces & levelsMask).none())
     {
+        // POC INSTRUMENTATION: log when the OR-aggregated early return fires
+        // for a cube map while at least one face per level is NOT redefined.
+        if (textureType == gl::TextureType::CubeMap)
+        {
+            for (uint32_t face = 0; face < gl::kCubeFaceCount; ++face)
+            {
+                if ((~skipLevels[face] & levelsMask).any())
+                {
+                    fprintf(stderr,
+                            "[POC-HIT] stageSelfAsSubresourceUpdates early-return DROPS "
+                            "cube face %u (levelsMask=0x%x skipLevels[face]=0x%x "
+                            "OR-aggregated=0x%x)\n",
+                            face, static_cast<unsigned>(levelsMask.bits()),
+                            static_cast<unsigned>(skipLevels[face].bits()),
+                            static_cast<unsigned>(skipLevelsAllFaces.bits()));
+                }
+            }
+        }
         return;
     }