Hi Zhu, referring to your statement:
If you use Upload, this will affect the client's environment.
If you use Change, this will only affect the development environment, you can do development, but after you close the development environment, the license will be restored to the original one.
I suppose only a development license then is useful to use the change button, since a normal NAV user license won't be able to edit anything even if change is been selected.
Thank you.