Migration best practices

Summary

We have several people working on the application in various areas with different deadlines than us, how do we ensure that everyone's changes get made?

Content

As the summary states, we have several different teams working in HCM Cloud, just to name two, we have the Core Group and Performance Group. The Core group works on the brunt of the application, but the Performance group only works on Performance and Goal management. This is because the Performance group handles other vendors that weigh on Performance and Colleague Profiles, such as our continuing education vendors. 

Now the challenge is that the Performance group has different deadlines for moving things from Dev to Test to Prod than the Core group does. Before the 19D update, they would just import and publish the sandboxes they downloaded from Dev. Since the ability to do that is gone, I've been trying to figure out ways to do migration where we only send out certain changes from certain published sandboxes. This is also due to the fact that some of the changes the Core group are making and publishing may not be ready to move to the next environment. I believe