SpamCop will not send reports for any spam it detects is more than 48 hours old, as indicated by the first accepted Received: line.
Short answer: because it is.
SpamCop uses the date of the topmost useful Received: line. This is usually information direct from your own email server, not the spammer's email system. The date used is actually appended by your own ISP and indicates the amount of time the email has been sitting in your inbox waiting for you to retrieve it. This part of the header cannot be forged to fool SpamCop. If there is a discrepancy in the date from the first "received" line it is due to a problem with your email provider's server. Either it is working very slowly or it has a clock that is out of sync.
Chances are that within two days, the spam will have been reported many times over (especially in cases of large spam runs). In fact, most spam reports are redundant after only a few hours. If an administrator is going to do something about the problem, he/she will already have done so or is in the process of doing so. Sending more reports at this point would just serve to bog down their already full inboxes, and the last thing we want to do is overburden the people whose help we need.
It is understandable that you want to "go on record" as having
received the spam, but it's just not practical. If you simply must
file a report on a message you can still do so manually.
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