Problem using reportbug for *FIRST* time

[Richard Owlett <rowlett@cloud85.net>]

When I attempted to send the bug the response was:

> Connecting to reportbug.debian.org via SMTP...
> SMTP send failure: (421, b'buxtehude.debian.org: Too much load; please try
> again later'). Do you want to retry (or else save the report and exit)?
> [Y|n|q|?]? ?
> Y - (default) Yes, please retry.
> n - No, save and exit.
> q - Quit.
> ? - Display this help.
> SMTP send failure: (421, b'buxtehude.debian.org: Too much load; please try
> again later'). Do you want to retry (or else save the report and exit)?
> [Y|n|q|?]? n
> Wrote bug report to /tmp/reportbug-timeshift-20200227-5343-vtejhfdd

For how long would it have been reasonable to continue retrying?
How do I resend it now (I've never knowingly used SMPT)?
Can I send it by e-mail using SeaMonkey?
If so, how do I handle the "X-Debbugs-Cc:" line?

TIA