The branch is out of date because it lacks recent changes from the base branch. Pull and merge or rebase these changes locally before updating the PR.

The 'This branch is out-of-date' warning in GitHub pull requests signifies that your feature branch doesn’t have the latest commits from the base branch, often main or master. To fix this, go to your local repository and pull the latest changes from the base branch with git pull origin main (replace main with the relevant branch name). After pulling, you have two options to integrate these updates: merge or rebase. A merge is straightforward, where you can use git merge main to bring the base branch changes into your feature branch, followed by committing the merge. Alternatively, you can rebase with git rebase main, which places your commits on top of the latest base branch commits, creating a cleaner history. Once you’ve updated your branch locally, push it to GitHub, and the 'out-of-date' warning should disappear. This approach keeps your pull request compatible with the latest code on the base branch, making integration smoother.