4581 - Error in date of plan line!
4581 - Error in date of plan line!
4581 - Error in date of plan line!
Marking parameter Check Plan Deadlines in Plan Period for plan document type a check is performed when entering dates in plan lines:

Trying to enter start or end date a check is run according to the following procedure:
1. At least one date must be entered. 2. In case you entered both dates the primary one must be inside the bounds of the plan period.
3. If only the start date is entered, it must be inside the bound of the plan period. 4. If only the end date is entered, it must be inside the bound of the plan period.
The error is returned if the date you entered does not match the above conditions.