The first thing is to start making alternative arrangements for your internet connectivity. Either extend the disconnection date of your current provider, or put something else in place for the intervening time.
Second, you'll likely need a manned installation for your VM services. You can arrange either by calling in, or waiting on this forum - that may take a couple of days.
Once you know the date of your manned install, then you can plan how long you need your existing connectivity for. Whether you want to allow some overlap is upto you, but it's probably a wise idea if connectivity is vital for you.
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