Dependencies & rescheduling
A dependency says that one task (the successor) has to wait for another (the predecessor). When a predecessor slips, the system helps you move the successors to match.
Adding a dependency
Open the task → Dependencies → Add → pick the predecessor, the constraint type and a lag (days, may be negative, up to ±365). In the Projects app you can also draw links directly on the Gantt chart.
- A task cannot depend on itself, and cycles are not allowed (A waits for B, B waits for A).
- By default only tasks in the same project can be linked; the organization can allow cross-project links.
The four constraint types
| Type | Successor may start when | Successor may finish when | Earliest successor date |
|---|---|---|---|
| FS — Finish → Start | Predecessor is done | Predecessor is done | Start ≥ predecessor due + 1 day + lag |
| SS — Start → Start | Predecessor has started | No constraint | Start ≥ predecessor start + lag |
| FF — Finish → Finish | No constraint | Predecessor is done | Due ≥ predecessor due + lag |
| SF — Start → Finish | No constraint | Predecessor has started | Due ≥ predecessor start − 1 day + lag |
Dates are counted as whole days. A cancelled or deleted predecessor no longer constrains anything. Subtasks inherit their parent’s start constraints.
When a task is blocked
Blocked cards and rows show a warning icon naming what they wait for. When you move such a task to In Progress or Done, depending on the organization’s setting:
- Off — no check
- Warn (default) — the system asks you to confirm, you may continue
- Block — the move is refused until the predecessor meets the condition
Rescheduling a dependency chain
Change the predecessor’s dates
When you move a task’s due date, add a new dependency, or drag a bar on the Gantt chart, the system computes which successors now violate their dates.
Review the proposal
A dialog lists the tasks that would move and their new dates. Each task keeps its duration; the system never pulls a task earlier, and never assigns dates to a task that has none.
Confirm
Click Apply to move the whole chain. Tasks that cannot be moved (outside your permissions, or breaking a parent’s date range) are listed separately — never silently skipped.
The organization picks one of three behaviours: Ask (default), Automatic, or Off.
Have old dependencies with wrong dates? On the project’s Gantt chart, use Reschedule by dependencies to get a fix proposal for the whole project, then confirm.