Set the expiration time for licenses per price option
<?php
/**
 * Plugin Name: Easy Digital Downloads - Variable Pricing License Expiration
 * Description: Set the expiration time for licenses per price option
 * Author: Pippin Williamson
 * Author URI: https://easydigitaldownloads.com/
 * Version: 1.1
 */

function pw_edd_sl_license_length( $expiration, $payment_id, $download_id, $license_id ) {

	$price_id = edd_software_licensing()->get_price_id( $license_id );

	if( $price_id !== false ) {

		switch( $price_id ) {

			case 1:
				$expiration = '+10 years';
				break;
			case 2:
				$expiration = '+2 years';
				break;
			case 3:
				$expiration = '+1 year';
				break;
		}

	}

	return $expiration;

}
add_filter( 'edd_sl_license_exp_length', 'pw_edd_sl_license_length', 10, 4 );
To implement this snippet on your site, create a brand new, empty WordPress plugin and paste the above code inside.