[skwirl]

You can create a new OmniPlan project, set the start date to "Undetermined" in the Project : Information inspector, then plan out your production tasks and resources as a generic template. When you're done, you can save this template by going to "File" > "Save as Template".

Now you'll be able to go to "File" > "New from Template" and select your pre-made template, complete with all the resources and tasks you've created. Just remember to set the project start date to something specific if you need to.