Planner unable to move certain work orders earlier on the gantt chart. Certain work orders can't be moved to an earlier position on the Gantt chart than their current placement. When attempting to move these work orders, the [planner automatically forces a change to the "Start No Earlier Than" constraint instead of allowing the work order to be rescheduled as intended.
Solution 1
When using some views, you can drag tasks behind fine. When selecting other views, you can't drag tasks backwards. This is because the majority of tasks in the relevant view are with a red flag, which means there is insufficient components available; awaiting for more material to be delivered by an supplier at a specific future date. If you drag a task that already has insufficient components, in between other tasks further back that also have insufficient stock, all the tasks will be create the components even later and will cause task overloads. This goes against the planning logic of Orchestrate. The insufficient components must be fulfilled before any backwards dragging can take place.
Also, The EarliestStartDate is used as a hard left-boundary during drag extent calculation. The PlanningStartDate / PlanStartDate acts as an absolute floor. Predecessor relationship constraints enforce additional left-boundaries. The drag clamping enforces the computed limits in real-time. The Multi-Task Editor also enforces the constraint on manual date entry.
Solution 2
To enable the task moving backwards and forwards (double-shuffles) during the task drag, please turn on system setting:
Drag Tasks Insert Successors
within Orchestrate System Manager.