If you look closely at the title of the Synchronize view you will see that we have started in Catch Up Mode (see #1). This is because there are changes in the stream that we should first integrate before releasing our own changes.
It is important to first catch up to changes made to the stream, retest with those changes loaded locally with your soon-to-be-released changes and then release your changes. By first taking the latest stream changes, and retesting, it helps to ensure that the changes you are about to release will actually work with the current state of the stream.