Hey guys, I am also in a trial version considering between a few project management software. I got a solution for this problem. It is not straight-forward, but a work-around…
Option 1. Making changes to the existing project
Marking the task “effort” or “duration time” to the actual time spent. This should adjust the timeline accordingly. A proper reporting on the time/resource management would also be generated. By doing this method, some workers could be highly rewarded by their productivity and production mangers would understand/value some workers :)
Option 2. Adding an old project
Step1. Expand the whole project (to view all the sub-tasks) and highlight all tasks.
Step2. Click on the Inspector -> Task -> Schedule and change the start date.
Considering you have done your dependencies correctly, all completed tasks would automatically fall back on the previous working-day/days. If you are way-ahead of schedule you should consider adding more than one working day, so that all completed tasks no longer show up on your timeline. This would also push the project timeline end date ahead :)