You can subscribe to any FT thread, no matter how old it is. Go to that thread, pull down the Thread Tools menu from just above the first post on that page toward the right side, and select Subscribe to this Thread. In the dialogue box that appears, select the type of notification you want - probably "instant notification" for this purpose. You'll be notified when there's a new post in that thread. You won't get any more notifications for new posts until you visit the thread.