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

# Maintenance Plans

> Generate traceable preventive work orders from a template, assets, and a fixed calendar cadence.

A Maintenance Plan is the scheduling definition for recurring preventive work. It combines one **Work Order Template**, between 1 and 100 **Assets**, a timezone-aware recurrence, and a planning horizon.

For every asset and occurrence inside the horizon, Canary creates a separate preventive work order. The work order starts as **Open**, uses the occurrence as its **Due Date**, and carries the template's title, description, priority, assignment, location, picture, and procedure snapshot when configured.

## Plan relationships

| Relationship         | Behavior                                                             |
| -------------------- | -------------------------------------------------------------------- |
| Work Order Template  | Supplies the versioned work-order defaults.                          |
| Assets               | Defines which equipment receives each occurrence.                    |
| Procedure            | Travels inside the template snapshot and attaches to generated work. |
| Occurrence           | Represents one asset at one nominal local date and time.             |
| Generated work order | Stores plan and occurrence provenance for traceability.              |

Only admins can create, edit, duplicate, pause, resume, archive, restore, backfill, or skip Maintenance Plan work.

## Calendar recurrence

| Recurrence | Configuration                                                            |
| ---------- | ------------------------------------------------------------------------ |
| Daily      | Every day at the anchor time.                                            |
| Weekly     | Every 1–52 weeks on one or more selected weekdays.                       |
| Monthly    | Every 1–12 months on day 1–31. Short months use their last calendar day. |
| Yearly     | Every 1–10 years on the anchor month and day.                            |

The **First nominal date and time** is a wall-clock value in the **Plan timezone**. Canary stores the IANA timezone with the plan so the cadence follows local calendar time through daylight-saving changes. A missing spring-forward time shifts to the first valid time after the gap; a repeated fall-back time uses the earlier instant. The schedule preview identifies these adjustments.

## Planning horizon

The **Planning horizon** controls how far ahead Canary materializes occurrences and generates work orders. It must be positive and no longer than one year: up to 366 days, 52 weeks, 12 months, or 1 year.

A wider horizon creates more future work earlier. A shorter horizon keeps the active work queue closer to execution. Canary continues rolling the horizon forward while an eligible plan is Active.

## Occurrence and plan states

An occurrence can be **Planned**, **Generated**, **Skipped**, or **Superseded**. The **Occurrence history** preserves these outcomes and links generated entries to their work orders.

A visible plan is either **Active** or **Paused**:

* Active plans can reconcile their horizon and generate work.
* Paused plans keep generated work and history while future generation waits.
* Resuming starts from the next future occurrence. Canary uses [Backfill missed work](/help/maintenance-plans/create-and-manage#backfill-missed-work) for deliberate historical creation.
* Archiving removes the plan from the active catalog and keeps its definitions, versions, occurrences, and generated-work provenance in recovery.

## Versioned history

Each saved definition becomes a plan version with a template, procedure, assets, recurrence, timezone, and horizon snapshot. Editing a plan supersedes affected future Planned rows. Generated work orders and earlier history retain the version that produced them.

Use **Version history** to understand definition changes and **Occurrence history** to follow planned, generated, skipped, and superseded work.

Next: [Create and manage a Maintenance Plan](/help/maintenance-plans/create-and-manage).