Hey there @rachel4green,
Thanks for this post! We and so happy to have you in the community!
When it comes to these types of changes on the packing slips, that information is absolutely available! You can check here for how to create custom packing slips and then subsequently use automation rules to establish that workflow to apply those custom packing slips automatically. You can also apply a default packing slip on a per store basis from the store settings as well!
The rules can be made by any account, but just as a heads up, you will need to be Silver subscription or higher to create custom packing slips.
I hope this helps!