Any reason to keep the USCIS account going and change the password each 60 days? This applies only after NVC receives the K1 petition.

I don't think the account will come into use until AOS. From NOA2 until the Visa, the case is in the hands of the State Department.

That was my thinking too. Do you think it would be of good use to keep it going until the AOS? I know once the password expires, then you have to set up a new account or something like that (reset the password maybe). Can you use the same email to set up the new account? Can you use the existing account if you keep it open for AOS?

I am familiar with computer systems, I would assume you could either reset the password if old one expired, or just create a new one when the time arrives for AOS, there should not be a block on using the email address before, the account is keyed to the user name that you entered, not email address.