The SpamCop blocking list now has its own FAQ section
The short answer is that you cannot be removed.
SpamCop automatically handles blocking and unblocking of ISPs. If SpamCop continues to receive reports of spam originating from the networks you are responsible for, those networks will continue to be blocked. If not, then you will be unblocked by SpamCop automatically after 24 hours.
If the SpamCop reports that you receive relate only to web-hosting for the spammer, then this does not count toward blocking. The email filters consider only complaints of sourcing spam.
If you have recently closed an open relay on your network, you should check and/or notify the various relay blocking systems in use:
Please only notify them if they have in fact detected and listed your open server.
You can check your listing status on over 150 blocking lists at DNS Stuff