Admins can assign a user (or any other entity) to a new group, while keeping the record of previously tracked hours in its corresponding group. In other words, if Bruce moves from HR to Marketing on October 11th, an admin can change the assigned group while keeping all of Bruce's tracked hours up until October 11th under HR.
This is done by establishing a timeframe in the “Groups” module, located on the individual entity pages (a person, project, or company page). If the Groups module does not appear automatically on an entity page, you can add it by clicking “customize” in the top right corner and dragging and dropping the module.
To set dates for a group assignment, click on the calendar icon to the right of the group name. You will be able to select one date, which will be considered the start date of the assignment. If there was another group of the same type already assigned (for example, "Countries" or "Departments"), this previous assignment will automatically be delimited.
Note that what was once referred to as the “Groups” module is now called “Group Settings” and can be found on the settings screen. Here you can add and edit all groups and subgroups for your organization.