# Edit a plan task and its dependencies

> Set a plan task's dates, length, milestone, assignee, progress, must-start date, deadline and cost, and link tasks with FS, SS, FF or SF links and lag.

Source: https://plexiidesk.com/help/plans-task-details
Section: Focus and flow > Tasks and plans
Plans: All plans
Updated: 2026-10-15

Every task in a plan has a details panel where you set what the schedule needs: when the task should start and finish, how long it takes, who is doing it, how far it has got, and which other tasks it waits for. The plan's timeline redraws as soon as you change anything.

Use it to turn a list of tasks into a schedule: give each task a length or dates, then link them in the order the work has to happen.

## Before you start

- You need a plan with at least one task. See [Plans: timelines for your rooms](https://plexiidesk.com/help/plans-overview).
- Task details are available on every plan.
- Every change saves as you make it. There is no Save button.

## Open a task's details

1. Open the plan and choose **Timeline**, **Board**, **Grid**, **Calendar** or **Workload**.
2. Click a task: its bar or name on the timeline, its card on the board, its row in the grid, or its name in the calendar or workload.
3. The details open in a panel on the right. Click another task to switch to it, or the **×** at the top of the panel to close it.

## The top of the panel

- **The task's name.** Click it to rename the task, then press `Enter` or click away.
- **Open task & files**: opens the task itself, with its notes and attachments.
- **Delete**: moves the task to Trash. An undo message appears briefly, in case you change your mind.

## Dates and length

| Field | What it does |
| --- | --- |
| **Planned start** | The earliest the task should start. A task it depends on can still push it later. |
| **Planned finish** | When the task should be done. This is also the task's due date everywhere else in PlexiDesk, such as All Tasks. |
| **Length in working days (used when no finish date)** | How many working days the task takes, from 1 day up to 3650. |

The schedule uses them like this:

- With both a **Planned start** and a later **Planned finish**, the task lasts the working days between them, and the length box is not used.
- Otherwise the task lasts the number in the length box.
- With neither, it lasts one working day.

To clear a date, delete it in its box. To clear the length, empty its box.

## Milestone

Tick **Milestone (zero-duration marker)** for an event rather than a piece of work, such as a launch or a sign-off. A milestone takes no time and shows as a purple diamond on the timeline. Its length, progress and cost boxes are hidden while it is ticked.

The plan's Overview counts milestones and shows the next one coming up. See [Plan views: Overview, Board, Grid, Calendar, Workload and Files](https://plexiidesk.com/help/plans-views).

## Assigned to

Type a name in **Assigned to** and press `Enter` or click away. As you type, PlexiDesk suggests teammates who are online now and people already assigned to tasks in this plan. You can also type any name, including someone who does not use PlexiDesk.

The name appears on the task's board card, in the grid's **Owner** column and in **Workload**. Leave it empty for **Unassigned**.

## Progress

Drag the **Progress** slider to show how far through the task is, in steps of 5%. The timeline fills that much of the task's bar, and the board and grid show the percentage.

Progress is for your own tracking. It does not mark the task finished: to do that, drag its card to **Done** on the board or change its status. A finished task always shows 100%.

## Must start on and deadline

- **Must start on** pins the task's start to that date, even if a task it depends on has not finished. Use it for work fixed to a date, such as an event booked for a particular day. Leave it empty to let the schedule decide.
- **Deadline (finish by)** does not move the task. If the schedule has it finishing after that date, the box turns red, **Scheduled to finish past the deadline.** appears under it, and the task gets a red calendar icon on the timeline and in the grid. The Overview counts these under **Missed deadlines**.

## Cost

Type a number in **Cost (for budget rollup)** to give the task a cost. The grid shows each task's cost and adds them up in a **Total** row. Costs have no currency, so use the same one across the plan.

## Link tasks

### Add a task this one depends on

Under **Depends on (finish first)**:

1. Choose the type of link in the small menu beside **Add a predecessor…**. It starts at **FS**.
2. If you want a gap or an overlap, type a number of working days in the box next to it (see Lag, below).
3. Choose the other task in **Add a predecessor…**. The link is added straight away, with the type and lag you set.

The other task appears in the list, with an arrow drawn between the two on the timeline.

### The four link types

| Type | Meaning | Example |
| --- | --- | --- |
| **FS** (finish to start) | This task starts after the other finishes. The usual choice. | Print the brochure after the design is approved. |
| **SS** (start to start) | This task starts once the other has started. | Start testing once building has started. |
| **FF** (finish to finish) | This task finishes once the other has finished. | Finish the review when the writing finishes. |
| **SF** (start to finish) | This task finishes once the other has started. | Keep the old system running until the new one starts. |

### Lag

The number beside each link is the lag, in working days:

- **0** (the default) means straight away.
- **A positive number** adds a gap, such as 2 to leave two working days after the other task finishes.
- **A negative number** lets the tasks overlap, such as -1 to start a working day before the other finishes.

### Change or remove a link

Each task in the **Depends on (finish first)** list has its own type menu and lag box. Change either and the schedule updates. Click the **×** at the end of the row to remove the link.

### Add a task that waits for this one

Under **Blocks (must finish before)**, choose a task in **Add a successor…**. It now depends on this one, with an **FS** link and no lag. To change that link's type or lag, open the other task and change it in its **Depends on** list. Click **×** beside a task to remove the link.

When nothing depends on the task, the section says **Nothing waits on this.**

### When a link cannot be added

- **That would create a circular dependency.** The other task already depends on this one, directly or through other tasks. A loop would mean neither could start.
- **That dependency already exists.** (or **That link already exists.**) The two tasks are already linked.

A task already in the list is not offered again.

## The schedule summary

The foot of the panel shows what the schedule has worked out:

- **Scheduled** and the start and finish dates.
- **On the critical path**, or how many days of slack the task has, such as **3 day(s) of slack**: how far it can slip before the plan finishes later.
- Once you have set a baseline: **On baseline**, or how many days **behind baseline** (in red) or **ahead of baseline** (in green) the task's finish is. See [Baselines, working days, levelling and export](https://plexiidesk.com/help/plans-schedule-tools).

## Common questions

### I set a planned start but the task starts later

A task it depends on finishes after that date, so the task waits. Check **Depends on (finish first)**. To fix the start regardless, use **Must start on**.

### The length box seems to do nothing

The task has both a planned start and a later planned finish, so its length comes from those dates. Clear the planned finish to use the length box instead.

### Are these links the same as Waits for in the Tasks widget?

No. A plan uses only the links you make here. **Waits for** in the Tasks widget, and the widget's **Start** date, are kept separately and do not move the plan's timeline. See [Tasks, desks and subtasks](https://plexiidesk.com/help/tasks-overview).

### Can a task depend on more than one task?

Yes. Add as many predecessors as you need. The task waits for all of them.

### I deleted a task by mistake

Click **Undo** in the message that appears, or restore it from Trash. See [Archive, trash and restore rooms and desks](https://plexiidesk.com/help/desk-archive-trash).

## Related tasks

- [Use the plan timeline](https://plexiidesk.com/help/plans-timeline)
- [Plan views: Overview, Board, Grid, Calendar, Workload and Files](https://plexiidesk.com/help/plans-views)
- [Baselines, working days, levelling and export](https://plexiidesk.com/help/plans-schedule-tools)
- [Plans: timelines for your rooms](https://plexiidesk.com/help/plans-overview)
- [Tasks, desks and subtasks](https://plexiidesk.com/help/tasks-overview)