A fundraising round will close automatically when it reaches 0 days left. Additionally, a company can choose to close a round early if they have met their set goal and would no longer like to wait until the final campaign day.
The close of a round does not mean investments are finalized, it simply means the public can no longer submit new investment requests. After the campaign closes to the public, companies could potentially be countersigning subscription agreements or rejecting investments in their queue.
Final procedures can take a few days before the final numbers are determined.