protected function set_expiration() {

		/**
		 * Filter the lifespan of user session data
		 *
		 * @since 4.0.0
		 *
		 * @param int $duration Lifespan of session data, in seconds.
		 */
		$duration = (int) apply_filters( 'llms_session_data_expiration_duration', HOUR_IN_SECONDS * 6 );

		/**
		 * Filter the user session lifespan variance
		 *
		 * This is subtracted from the session cookie expiration to determine it's "expiring" timestamp.
		 *
		 * When an active session passes it's expiring timestamp but has not yet passed it's expiration timestamp
		 * the session data will be extended and the data session will not be destroyed.
		 *
		 * @since 4.0.0
		 *
		 * @param int $duration Lifespan of session data, in seconds.
		 */
		$variance = (int) apply_filters( 'llms_session_data_expiration_variance', HOUR_IN_SECONDS );

		$this->expires  = time() + $duration;
		$this->expiring = $this->expires - $variance;

	}