> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hamla.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Message timing

> How often one person hears from your automatic campaigns, what happens when two want them on the same day, and what 'waiting' means on a campaign.

An **automatic campaign** sends when something happens: a person signs up, starts a trial, enters a segment, submits a form. Several can be live at once, and they often fire for the same person close together. Signing up and starting a trial are minutes apart.

So that nobody gets a burst of messages, all of a business's automatic campaigns share one limit per person.

## The limit

| Rule | Value |
| - | - |
| Automatic campaigns that reach one person, in any 24 hours | 1 |
| Automatic campaigns that reach one person, in any 7 days | 3 |
| Send window for a message that waits, from the moment its campaign fired | 48 hours |
| Send window for a birthday greeting | 12 hours |

The limit counts **campaigns, not emails**: it decides when an automatic campaign may start for a person. Once it has, that campaign's own follow-up steps ("if no trial started, wait 2 days, then…") keep the timing you gave them and are never held back. So a three-step series counts once.

What the limit does not cover:

* a campaign you send yourself, to a list;
* order updates such as "your order shipped" or "delivered", which the person is waiting for.

A **birthday** campaign is covered, with a shorter wait: if the person has no free slot on their birthday, the greeting is not sent, because "happy birthday" a day late reads like a mistake.

## A message over the limit waits, it is not dropped

When a campaign fires for someone another automatic campaign already reached that day, its message **waits for that person's next free slot**, usually about a day after the last one. It goes then.

Before it goes, Hamla checks again whether it still makes sense. It is **not sent** when, while it waited:

* the person already did what the campaign was for (its goal);
* the person left the segment that triggered it;
* the campaign was paused, ended or deleted;
* or no slot came within the send window above.

A message that was not sent this way is recorded with its reason. It does not stop the same campaign from reaching that person later.

## What you see on a campaign

The campaign's results show how many messages are **waiting** and when the next one goes, and how many waited and were then **not sent** because they no longer applied.

If a message arrived a day later than you expected, another automatic campaign most likely reached the same person first that day. Hamla tells you this when it builds an automatic campaign that shares people with one already live, and it can merge the two messages or change their order.


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