The report is refreshed at the point in time your email is sent to the report. The workflow looks like this:
- The report is run to get Contact/Lead IDs to send to (other fields in your report are ignored).
- The values of all the fields mapped in "Email -> Subscribers -> Profile Managment" are retrieved for all the leads/contacts in your report.
- A new temporary Data Extension is created and the data retrieved in the previous step is imported into it.
- The email is sent to the temporary Data Extension.
If you send a second time to the same report, the above process repeats itself, a new Data Extension is created and you send to the new temporary Data Extension.
I don't see a scenario where the email address of the lead/contact is dropped in favour of the report owner, unless you've done something strange with the report type and re-labeled the record owner field in your report to "Lead Id" or "Contact Id".