First, navigate to the Jira project settings page and click on the "Behave Pro" in the left navigation menu. You will be shown the Behave Pro settings for your Jira project.

To disable your Jira project that is currently using a git inregration, click on the green toggle button in the right top corner.

Next, you will be prompted with a confirmation dialog. Click "Disable" button.

After that you will be redirected to the configuration page as shown in the screenshot below, click "Getting Started" at the bottom.

Next, choose the "classic" workflow as shown below.

That's all for setting up a classic Behave Pro for your Jira project.

Next, to bring back the Feature files from your git repository, simply go to the Specifications page by clicking on the "Specifications" link from the main top navigation bar. Next, select the correct Jira project and click the upload icon as shown in the screenshot below. Finally, upload the feature files from your git repository. 

That's all.