That's not likely their setup. If they're leasing the servers, they should have full admin control of the servers. If not, they will have had pre-release queues set up and they push the button to allow the updates to go live. Either way, it's like 95% chance that WC are the ones delaying.
And having worked with servers of all types, setting them up fing sucks. It can be broken so easily and it can often be easier to do a reset than try to figure out your problem. So likely there's some issue which is preventing them deploying them all.
The problem with this is the fact that they are a business. They should have had the new servers up and stable 2-3 days ago and simply not visible to the server lists. To ensure they are ok, can handle load, there's no unforeseen memory leaks, etc. Then they should have had a feature flag that turned them on at release time or a minor, minor patch to activate them on people's guis. This not being live, constant push back is really not the way to approach it.