I don’t think this is a common problem at all. In fact, maybe that’s one way to convince management. Explain to them that it’s highly unusual to have 200+ servers with no dedicated maintenance window. EVERY company needs a maintenance window to do maintenance. Just like you need to take your car to the mechanic periodically to do preventive maintenance. I have never heard of a company with 200+ servers and no maintenance window. They are asking for trouble.