In a Gantt chart, schedule constraints are limitations on when certain activities can begin or end.
Constraints can help project managers ensure that a project stays on track and is completed on time. However, too many constraints can limit flexibility and make it difficult to adjust the project schedule if unexpected changes occur. Therefore, it's important to strike a balance between using constraints to ensure project success and allowing for some flexibility to accommodate changes.
By default new phases that are not linked have no constraints
If a linked phase had been previously edited it will default to Start No Earlier Than, which was the case with phase #2. If a phase is new and has not been edited it will default to As Soon As Possible once linked, which is the case with phase #3
Phases with constraints can be moved forward, but not backward
To move a phase with a constraint backward you'd have to adjust the predecessor to display a lag. In this case I adjusted the predecessor to read 2FS-2d (finish to start minus 2 days)
If a phase with a constraint is in the future you can make it revert back to its original position by adjusting the constraint to read As Soon As Possible
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