The limits and why they exist.
THE HARD LIMITS
Shared hosting enforces an hourly sending limit. A campaign to a few hundred subscribers will be interrupted partway.
WHY THE LIMIT EXISTS
One account sending in volume affects the sending reputation of every account on the server.
A campaign generating complaints damages delivery for everyone.
WHAT ELSE IS MISSING
No bounce handling, so invalid addresses are retried indefinitely No unsubscribe management, which is a legal requirement in most places No delivery reporting No reputation management No warm-up of sending volume
WHAT HAPPENS IF YOU TRY
The send stops partway. Some subscribers receive it, some do not, and you cannot tell which.
Repeated attempts damage your domain's reputation.
THE LEGITIMATE ARRANGEMENT
Use a sending service. Configure its SPF and DKIM records for your domain.
Your mailboxes stay with us for correspondence; campaigns go through the service.
That is the correct separation, and it is what every serious sender does.
