PTF-What are best practices to update and save existing test cases?

We have created a Project for all PTF test cases and queries in app. designer, in one of the lower environment.

When ever I make changes/updates to existing test cases, is saving the test case in client enough ?

or do I have to insert that test case into existing project every time I change ?

In the past, I was saving all the changes made to PTF test cases in client and didn't do anything in app designer. When the project was exported to a different environment, noticed that changes were not captured.

Thanks for your help!