Our engineers wrote a script that should take care of this issue. However, the script only runs weekly so as to conserve system resources.
So if threads show inaccurate page counts, the issue should resolve within a week or so. If that doesn't happen for a particular thread, feel free to call it out here.
The more pages a thread has, the more likely it is to experience this issue. If you see a thread heading towards the long side, feel free to start a mk 2 version of the thread with links to and from the original thread. That will help prevent the issue from recurring.