_reset_front_page_settings_for_post( int $post_id )

Source

File: wp-includes/post.php

function _reset_front_page_settings_for_post( $post_id ) {
	$post = get_post( $post_id );

	if ( 'page' === $post->post_type ) {
		/*
		 * If the page is defined in option page_on_front or post_for_posts,
		 * adjust the corresponding options.
		 */
		if ( get_option( 'page_on_front' ) == $post->ID ) {
			update_option( 'show_on_front', 'posts' );
			update_option( 'page_on_front', 0 );
		}
		if ( get_option( 'page_for_posts' ) == $post->ID ) {
			update_option( 'page_for_posts', 0 );
		}
	}

	unstick_post( $post->ID );
}