"The source directory is empty" shown when master branch is empty

When we occasionally have an in-development project, the master branch will be empty till we're ready to launch.

Visiting a URL in this format:
https://bitbucket.org/username/projectname/src

Shows the following message:
"The source directory is empty.
Get started with your first commit."

There's no quick way to switch branches on that page, to view the develop branch.

I know there are other ways to get the /develop branch to display, but this is a bit unintuitive and the warning message on this screen is confusing to a lot of users.