If you’ve got some projects which can be moved and some which can’t, it makes sense to plan first for the un-moveable ones, and see how many people you need for those. That’s a given, it’s fixed. Then you know how many people you have left, for the moveable ones, so you can work out how fast (or slowly!) you can do the moveable ones…..
Once you understand this you’ll see how important and how great it is!
If you want to know more about this then check out my comprehensive course on Linkedin Learning – it really does do this subject fully, and clearly.