I used to report a lot of spam to SpamCop
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until ntlworld.com, now virginmedia.com, started altering the headers in same way so that SpamCop can no longer process any mail received from them. However, as their spam filtering vastly improved at the same time, receiving spam is now a very rare event, so no problem.
More recently, several people have observed that reporting spam to SpamCop is a waste of time but I received a spam email on a non ntl/VM account timed at 01:16 this morning, so I posted it to SpamCop a few minutes ago and received this response:
ISP has indicated spam will cease; ISP resolved this issue sometime after Thu, 24 Jan 2019 07:30:21 GMT
So, I will continue to post these scams to SpmCop when I receive them!