PPM Express supports two task types for PPM Express tasks: Flexible and Fixed Units. Together with Calculate Progress by, Task Mode, assignment Units, and Effort Driven, these settings determine how Effort, Duration, and resource assignments behave when task information changes.
This article explains how the settings relate to one another and which scheduling behavior you get with each configuration.
Calculate Progress by setting
The first setting that determines which scheduling options are available is Calculate Progress by in Project Settings > Schedule Calculation for PPM Express Tasks.
If Calculate Progress by = Effort, you can choose either Flexible or Fixed Units as the Task Type.
If you select another progress calculation method, such as Story Points or Average Progress, the Task Type is automatically set to Flexible and cannot be changed. Fixed Units scheduling is therefore available only for projects that calculate progress by Effort.
Default Task Type
When Calculate Progress by = Effort, the Task Type setting becomes available. You can select:
Flexible: Effort, Duration, and assignment Units can adjust according to the latest scheduling change. Use this when you want PPM Express to adapt resource participation to the planned work and schedule.
Fixed Units: Each assignee's Units remain fixed unless you explicitly change them. Duration or Effort recalculates around the fixed resource participation.
The Task Type selected in Project Settings is the default for new tasks. Changing this project setting does not recalculate existing tasks.
The project setting defines the default, but tasks within the same project do not all have to use the same type.
For an individual task, use Set Task Type -> Flexible or Set Task Type -> Fixed Units from the task menu. You can also select multiple tasks and use Set Task Type from the toolbar.
This means, for example, that a project can use Flexible by default while selected tasks that require capacity-based scheduling use Fixed Units.
Assignment Units (partial assignments)
Both Flexible and Fixed Units tasks support Units for individual assignees.
Units indicate how much of an assignee's available working capacity is allocated to the task (in %).
Calculations will reflect resource working calendars, resource availability, Max Units, Non-project Work, and assignment Units.
To review or set Units for resources, open a PPM Express task and select the Assignments tab.
Here you can manage task assignees and their Units directly in the task panel while keeping assignments synchronized with Assigned To. Define an assignee’s participation as a percentage of their available working day, supporting part-time allocation, full-time allocation, and over-capacity planning.
The Resource Workload view then reflects the distribution based on the assignment load set on the Assignments task tab.
For Flexible tasks, if the planned work exceeds an assignee’s available capacity, PPM Express keeps the task’s Effort and Duration unchanged and adjusts the assignee’s Units instead. The Units value therefore represents the level of daily participation required to deliver the planned effort within the existing task duration.
After Units are adjusted, PPM Express recalculates the task’s distributed effort in the Workload view using those Units. This makes the workload distribution consistent with the resource’s planned participation rather than simply spreading hours evenly across the task duration.
For example, if one assignee has an 8-hour working day but a one-day task contains 12 hours of effort, the task can remain one day with 12 hours of effort while the assignee’s Units become 150%. The Workload view then reflects the distribution based on that updated assignment load.
For Fixed Units tasks, the assignee’s Units represent a fixed level of daily participation and are not automatically adjusted when planned work changes. If the planned Effort cannot be completed within the current Duration at the specified Units, PPM Express keeps the assignee’s Units unchanged and recalculates the task’s Duration instead. This follows the Fixed Units model, where changing Effort recalculates Duration while Units remain fixed.
After Duration is recalculated, PPM Express redistributes the task’s effort in the Workload view across the resulting working period according to the assignee’s fixed Units and available working capacity.
For example, if one assignee has an 8-hour working day, is assigned at 100% Units, and the task contains 12 hours of Effort, PPM Express keeps the assignee at 100% rather than increasing the Units to 150%. The task’s Duration extends to accommodate the 12 hours of work at the resource’s fixed capacity. The Workload view then distributes those 12 hours over the recalculated task duration based on the assignee’s 100% Units.
Effort Driven setting
When a task is Fixed Units, an additional Effort Driven setting becomes available.
You can configure it in Project Settings for new Fixed Units tasks -> Effort Driven -> Yes/No.
Effort Driven answers a specific question:
What should PPM Express preserve when assignment capacity changes?
- Effort Driven = No: Duration remains unchanged; Effort recalculates.
- Effort Driven = Yes: Effort remains unchanged; Duration recalculates (Effort Driven applies only to Fixed Units tasks).
Effort Driven setting can also be changed for individual Fixed Units tasks using Effort Driven > Yes/No.
Task Mode: Auto or Manual
Task Type and Task Mode are separate settings.
A task can therefore be Auto + Flexible, Auto + Fixed Units, Manual + Flexible, or Manual + Fixed Units.
For Auto Fixed Units tasks, PPM Express uses the scheduling relationships described above to recalculate Effort or Duration.
For Manual tasks, Fixed Units formulas are not automatically applied in the same way. Scheduling values remain manually editable, and manual-task distribution behavior is preserved.
When you switch a Manual task to Auto and PPM Express needs to reconcile its existing scheduling values, the Changing Task Mode dialog lets you decide what to preserve:
- Keep Effort & Units -> recalculate Duration
- Keep Duration & Units -> recalculate Effort
- Keep Duration & Effort -> recalculate Units
