Kevin/Ktrainhurricane,
This board in its current design* doesn't send notifications on replies to posts. Users must come back to view threads of interest to check for replies. An upgraded/paid user account enables Wash/Rinse/Spin indicators beside each thread on the index pages, which change color to indicate Wash/red for a new thread the user hasn't viewed, Rinse/yellow for a new reply in a viewed thread, and Spin/blue for a viewed thread with no replies ... but it still doesn't send notifications.
* The webmaster of the site, who custom-wrote the code, announced today that he is retiring from running it. The service that is taking over the operation probably will transition the board at some point to an updated format with new features.