diff --git a/scripts/Upload-Image.ps1 b/scripts/Upload-Image.ps1
index d5f02f9..537ecf2 100644
--- a/scripts/Upload-Image.ps1
+++ b/scripts/Upload-Image.ps1
@@ -5,7 +5,10 @@
 # 1. Checks the MCL cache before sending anything:
 #    - exactly one <OS>-Production.tag at the cache root (MCL writes it only
 #      when a run finishes; none = an unfinished or interrupted cache)
-#    - no Control file newer than that tag (MCL still writing / crashed)
+#    - OperatingSystem.json / HardwareDriver.json not newer than that tag
+#      (MCL still writing / crashed). The other Control JSONs are MCL's
+#      catalogs, which MCL 2.1 downloads again whenever it returns to its
+#      start screen, so they are newer than the tag in a good cache.
 #    - the OS in OperatingSystem.json is the one in user_selections.json
 #    - every Control / Tools JSON is non-empty and parses
 #    - every WIM, update and driver pack hashes to the SHA-256 MCL's own
@@ -177,8 +180,12 @@ try { $tagTime = New-Object DateTime ([BitConverter]::ToInt64($tagBytes, 0)) }
 catch { Stop-Cache @("MCL tag $($tag.Name) holds no valid time. Run MCL again.") }
 $tagOs = $tag.BaseName -replace '-(Production|QA)$', ''
 
+# Only the files a run writes for its selection. The catalogs (os.json,
+# packages.json, hw_drivers.json, boot.json, ...) are re-downloaded each time
+# MCL 2.1 goes back to its start screen, seconds after the tag.
+$runFiles = @("OperatingSystem.json", "HardwareDriver.json", "LanguagePacks.json")
 $late = @(Get-ChildItem -LiteralPath $ControlPath -File -ErrorAction SilentlyContinue |
-          Where-Object { $_.LastWriteTime -gt $tagTime.AddSeconds(5) })
+          Where-Object { $runFiles -contains $_.Name -and $_.LastWriteTime -gt $tagTime.AddSeconds(5) })
 if ($late.Count -gt 0) {
     Stop-Cache (@("These Control files are newer than the MCL finish tag ($tagTime):") +
                 ($late | ForEach-Object { "  $($_.Name)  $($_.LastWriteTime)" }) +
@@ -254,6 +261,12 @@ function Get-OsIds { param($e) if ($e.aOsIds) { return @($e.aOsIds) } return @("
 $matchedPkgs = @($pkgJson | Where-Object { (Get-OsIds $_) -contains "$selectedOsId" -and $_.enabled -eq 1 })
 $pkgTotalSize = [long]0
 foreach ($pkg in $matchedPkgs) { $pkgTotalSize += $pkg.size }
+# MCL 2.1 lists updates it never downloads (seen: the KB5043080 checkpoint CU).
+$missingPkgs = @($matchedPkgs | Where-Object {
+    $pd = Resolve-DestDir $_.destinationDir
+    $pr = if ($pd) { Join-Path $pd $_.fileName } else { $_.fileName }
+    -not (Test-Path -LiteralPath (Join-Path $CachePath $pr) -PathType Leaf)
+})
 
 # Drivers: match selected model IDs (family) + OS ID, deduplicate by path
 $allMatchingDrivers = @($driverJson | Where-Object {
@@ -284,7 +297,10 @@ Write-Host ""
 Write-Host "  Upload Plan (from user_selections.json):" -ForegroundColor Cyan
 Write-Host "  ------------------------------------------"
 Write-Host "  OS:        $($osv.marketingName) $($osv.productName) ($(Format-Size $osTotalSize))" -ForegroundColor Green
-Write-Host "  Packages:  $($matchedPkgs.Count) update(s) ($(Format-Size $pkgTotalSize))" -ForegroundColor Green
+Write-Host "  Packages:  $($matchedPkgs.Count - $missingPkgs.Count) update(s)" -ForegroundColor Green
+foreach ($mp in $missingPkgs) {
+    Write-Host "  WARNING:   packages.json lists $($mp.fileName) for this OS, but MCL did not download it. Not sent." -ForegroundColor Yellow
+}
 if ($IncludeDrivers) {
     Write-Host "  Drivers:   $($driverDirs.Count) model(s) ($(Format-Size $driverTotalSize))" -ForegroundColor Green
 } else {