Looking at the sentence below,

Is the semi-colon or colon used well?

Is the semi-colon or colon an effective choice in the writer's sentence? Why or why not?

What alternatives would you suggest, if any?

Sentence:

The Red Team did not put a tracking beacon in the emails to track forwarding of the phishing emails. But, the team reported that the target server collected email addresses and IP addresses for over 1500 external recipients within 24 hours of the original mailing; at that point, the target server was shutdown.

This sentence used a semi-colon due to both the sentences being independent but related to one another.