When creating or editing a project, you have the option to set a fixed time budget and toggle on the email alert to receive notifications when a certain threshold from the project budget has been reached/tracked.
NOTE: The email notification will be sent to the project managers of the project.
You can set a time budget reminder at a task level as well. Just hover over a task → Full task details → Check Time Budget Alert, then set the percentage.
There's also a Due Date Alert option to be notified a couple of days before the task due date.
NOTE: Emails will be sent to the assigned users and the project managers.