The first correspondence timeout counts towards your rating. After this, the player is tagged with a “recently timed out” marker and all subsequent correspondence timeouts are annulled until the player wins their first correspondence game that has lasted longer than 24 hours (note that this game didn’t need to start after the timeout, only the total time is relevant). After this, the “recently time out” marker is removed and the player can once again lose rating points through means of a timeout.
Anyone can gain rating points at any time from a correspondence timeout win, as long as both players have played at least 1 move and the loser is not already branded with a “recently timed out marker”