Date restrictions

If you apply a restriction to a project line, it will take precedence over any relationships with other lines and the project start date. As restrictions enable you to control the standard planning in more detail, they always have higher priority.

The examples below are all based on a project without restrictions:

• The project start date is the 16th. The first subproject has three activities.
• Activity 1 is the predecessor of activity 2. The lead time is 3 days.
• Activity 2 does not overlap with activity 1. The lead time is 4 days (weekend days are not work days).
• Activity 3 must end at the same time as activity 2. The lead time is 1 day.

This will look like this in the Gantt chart:

Now restrictions are applied to demonstrate the impact they have on the planning.

Must start on/Must end on

The restrictions 'Must start on' and 'Must end on' are not affected by relationships or the project start date. The example below shows what happens if you apply these restrictions to the example project.

You apply the following restrictions:

• Activity 2 will have the restriction ''Must start' on the 17th'.
• Activity 3 must end at the same time as activity 2, but the restriction 'Must end on' prescribes that it must end on the 19th.

This will look like this in the Gantt chart:

Activity 2 starts on the 17th, which means that it now automatically overlaps with activity 1. Activity 3 has a finish-to-finish relationship with the second activity, but must end earlier. And this is also what happens.

Do not start before / Do not start after / Do not end before / Do not end after

The project is adjusted, as is shown in the examples below:

• Activity 2 cannot start before the 20th.
• Activity 3 cannot finish before the 24th.
• Once activity 3 has completed, the first activity of the second subproject can start, so these two activities will have a finish-to-start relationship.
• Activity 3 will have the restriction ''Do not start before' the 27th of the month'.
• A second activity with a three-day lead time is added to the second subproject. This activity cannot start after the 30th.

This will look like this in the Gantt chart:

There will be a waiting time between activity 1 and activity 2. Activity 3 will finish as specified by the restriction; the finish-to-finish relationship with the predecessor has lower priority. This results in a waiting time between activity 3 and the first activity of the subproject, because this activity cannot start before the 27th.