// Disable all core updates
add_filter( 'automatic_updater_disabled', '__return_true' );

// Disable theme updates
remove_action( 'load-update-core.php', 'wp_update_themes' );
add_filter( 'pre_site_transient_update_themes', '__return_null' );

// Disable plugin updates
remove_action( 'load-update-core.php', 'wp_update_plugins' );
add_filter( 'pre_site_transient_update_plugins', '__return_null' );

// Disable automatic updates for plugins
add_filter( 'auto_update_plugin', '__return_false' );

// Disable automatic updates for themes
add_filter( 'auto_update_theme', '__return_false' );

// Disable automatic updates for WordPress core
add_filter( 'auto_update_core', '__return_false' );