Seriously I think you need something like mailchimp or a better mail host.

Businesses in the actual world use webservers internally or via their hosting solutions. When they fail to have adequate resources or technical staff proficient to implement inhouse solution, then they hire contract companies like constantcontact & mailchimp for marketing or newsletters.

Otherwise they (other businesses), like us, would have no ability to have: auditing breadcrumb trail email client records archives sender validation - which user has sent an email. If we ever are subject of a lawsuit there would be no repository. Legally, as a corporate entity, we are obliged to maintain the above.

The webhost we use is fine, I can ask them to raise the hourly limit, but it really isnt necessary. Most webhosts limit outbound emails to sub 500 outbound mails per hour to prevent being blacklisted as spammers. Or the webshosts have tools as described in the question - phplist or similar solutions as thottling solutions - It also helps to balance server resources.

However those are technical solutions which require a modicum of intelligence, patience and attention to use effectively are not viable when most users are typically morons that cannot handle more that 1-2 steps to accomplish a task. Hence attempting to find a t-bird addon solution or configuration parameter I have missed.

So thank you for input, but I would prefer an answer to my question.

The Send Later add-on might be a simple but effective means of scheduling your outgoing mail.

As your say, businesses in the real world have in house servers, and so run their own mail server software and set their own outbound limits. Just as the mail server that sat in my study until it died recently managed my mail. I had no limits set by a host, because I was the host.

Your talking of breadcrumbs and audit trails. If you have 9 users of a mail account, you have no audit trail. You have a collection of individuals you can point to who might have done it. So what is needed is a separate email account for each of these people, simply to establish an audit trail. They can all use a Display name of from the office of the board or whatever. But you have to be able to easily identify exactly which board member sent the mail. Believe me. I have been in the situation where boards members are finger pointing at one another over impropriety. They look to the IT guy and fire him, or try to, when they don't get the proof they want. I am guessing you would not have the issue if you had 9 email accounts as most sending limits are per user or mail account, not per Domain.

Delivery of mails with 150 recipients is becoming more and more of an issue as well, as I am sure you are aware. It is sort of accepted practice to use a mailing service for more that 50, hence my reference to mail chimp as their service for small users is free. It is a service I became aware of here in the first place. I have no use for such.