In one of my work, there was a requirement to uncheck the option for 'Generate automatic url alias' checkbox for all nodes. I used the Pathauto module with version 7.x-1.2 for handling standard urls in the site. When changing a node title, its URL automatically changes. In case one forgets to uncheck the option 'Generate automatic url alias' in the node editing form, you can uncheck the option with the following steps:
- Go to 'admin/config/search/path/settings' page.
- In Update action section, select the option 'Do nothing. Leave the old alias intact'.
- And save the configuration.
This way you can uncheck 'Generate automatic URL alias' option for all nodes instead of any form alters. Hope this helps to handle node's urls.