Pergunta:
Existe alguma desvantagem em usar a atualização offline do Windows?
Resposta:
Sim, existem desvantagens:
On both sides, i.e. for download and installation parts, WSUS Offline Update uses Microsoft's update catalog file wsusscn2.cab to dynamically determine the required patches. This catalog file contains at least all the updates classified as "critical" and "security relevant", but it does not necessarily contain all "important" and "optional" ones.
Concordo com @Ramhound dos comentários, não recomendo.
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