Restrict Content Pro - Prevent subscription downgrades

jp-rcp-prevent-subscription-downgrades.php

function jp_rcp_prevent_subscription_downgrades( $levels, $user_id ) {

	if ( ! is_user_logged_in() ) {
		return $levels;
	}

	$existing_level = rcp_get_subscription_id( $user_id );

	if ( empty( $existing_level ) ) {
		return $levels;
	}

	foreach ( $levels as $key => $level ) {
		if ( rcp_get_subscription_price( $level->id ) < rcp_get_subscription_price( $existing_level ) ) {
			unset( $levels[$key] );
		}
	}

	return $levels;
}
add_filter( 'rcp_get_upgrade_paths', 'jp_rcp_prevent_subscription_downgrades', 10, 2 );