22 Apr 2016

Rescheduling Revisited: Can Your App Do That?

by | posted in: APS, Capacity Planning, CPM, Enterprise Resource Planning (ERP), Hospitality Industry, Manufacturing, MES, MRP, PERT, Planning, Project Scheduling, Resource Allocation, Scheduling, Scheduling & Resource Management, Supply Chain, Uncategorized | 0

In a previous post (look here), I pointed out that scheduling is really just a special case of rescheduling. If you can modify part of an existing timeline without affecting other parts, you can easily modify—or create an empty timeline. So the real challenge for selecting a scheduling app is to find one that does a superior job of rescheduling.

To identify these requirements, you need to understand what makes you need to reschedule. For example:

  • Something breaks;
  • Someone is sick or just doesn’t show up;
  • Things take longer than planned;
  • Something takes on a higher priority;
  • An unexpected shutdown (snow day, rain out, power failure, etc.); or
  • Quality control requires a “do over.”

Therefore, rescheduling usually requires a sequence of steps something like this:

  1. Identify the activities that are directly affected by the new circumstance and unschedule them.
  2. Find all the other activities that are somehow linked to the activities that you just unscheduled. Unschedule them too.
  3. Redefine the circumstances. For example, change the availability of resources, change an earliest start times for certain activities, use a different sequence of activities, change an activity’s duration, and so on.
  4. Reschedule in the new environment, and do so around the activities that you didn’t unschedule.

Now look at some functional requirements for any scheduling app that is supposed to alleviate the headaches derived from this process.

With regard to Step 1:

  • The app should help its user to find all the scheduled activities that use a specified (now disabled) resource.
  • The app should also help find all activities not yet scheduled that use the same resource.
  • The app should help the user find all activities that are scheduled between specified dates or times.

With regard to Step 2:

  • The app should help the user find all activities that have a timing or sequence relationship with any of the activities found in Step 1.
  • The app should help its user find any activities that have a tag value (e.g. common customer, order number, due date, location, etc.)

With regard to Step 3:

  • The app should make it easy for the user to change the parameters that describe any activity.
  • The app should allow mass changes with one action. That is, it should allow common changes to be made to many activities all at once.
  • The app should store and retrieve multiple sequences or routings that can be used as alternatives when rescheduling is necessary.
  • The app should permit easy changes to the availability profile for any resource.

With regard to Step 4:

  • The rescheduling app should be able to fill holes in existing schedules.
  • The app should be able to show its user all times and resource combinations that permit an activity to be re

If the app you are using, or are considering, can do all of the bullet items above, you have a scheduling app that reschedules like a pro scheduler needs. Make sure you run it through the paces of your specific organizational needs before you commit. You’ll be glad you did.