1) Is there are a way to do something like:
$recipients->addTo("firstname.lastname@example.org", "AZT Webmaster");
to set the email address and the name belonging to the e-mail address for the sender?
Api docs wrote:
void addTo (mixed $address, [string $name = null])
2) I have a distribution list of 1300 people. Is it best to send out 1300 e-mails, or group them in groups of, say, 100 per e-mail, sending out 13 e-mails? Of course, I'd use BCC when applicable.
My understanding is that BCC'd emails are more likely to end up in a spam folder, however if it works ok in your case - by all means try to offload sending process to the smtp server - meaning 'bcc:<1300 recipients>' is a preferred method from the performance standpoint.
3) Is there a limit of how many e-mails or e-mail address one can send to within a specified timeframe? When experimenting with PhpMailer, it stopped working at 900, regardless if I sent them one at a time or in groups of 100. Maybe I wasn't waiting long enough between messages, or something else that I'm not aware of.
This would likely depend on the smtp server settings.