Unanchored, Anchored and Blocked Activities

Unanchored Activities will move automatically if a change is made that affects the period where the Unanchored Activity is placed. This Activity will move in accordance with the following rules:

• An Unanchored Activity moves forward in time automatically as an Activity is inserted or an Activity or Unavailable Period has been extended prior to the Unanchored Activity.
• An Unanchored Activity moves backwards in time automatically as an Activity is removed or an Activity or Unavailable Period has been shortened prior to the Unanchored Activity.
• How far the Unanchored Activity can move backwards depends on whether the Activity is ahead or prior to the current date and time.  
• If the Unanchored Activity is ahead of the current date and time this Activity will move backward automatically to any Unassigned Periods prior to its current placement but no further than an Unassigned Period that is part of the current date and time.
• If the Unanchored Activity is prior to the current date and time this Activity will move backward automatically to the start of any adjacent Unassigned Periods.

Anchored and Blocked Activities do not move automatically.  The difference between an Anchored Activity and a Blocked Activity is for a Blocked Activity any Unanchored Activities after the finish time of this Activity do not automatically move to an earlier time if there is space available to do so.

For Anchored and Blocked Activities that are divided into a series of parts, only the Start of the whole Activity (that is, the Start of the first part) is locked.  All other Activity parts behave as if they are Unanchored.