The answer is threefold:
- In preparation for the upcoming software update, the databases and user caches have been rebuilt. As a result of the previous forum rebuilds and consolidations, there were a lot of 'orphan' threads that had not been properly cleaned up in the database. There's also a known issue with Xenforo where post count totals are not being properly rebuilt in the cache. This has now been remedied with a workaround.
- Posts in some of the off-topic areas no longer count toward post and like totals.
- This forum has a really large database. And if there are problems running the various cache rebuilds, it may be necessary to revert to a previous database backup, causes a small amount of data loss. If that happens, you may notice several days of lost posts once the forum is re-opened. Obviously, this would further affect post counts as well as likes.
I should also mention that as I have outlined elsewhere, the upcoming 2.1 update is a fairly significant update that adds some new functionality and changes the way a few of the existing features work. So it's entirely possible those counts could be further adjusted once the update is applied. I'm especially interested to see what it does to the like totals when the new 'Reactions' add-on is installed. My guess is it won't change the statistics much during the install, but over time people will start to notice a difference as users discover the unlike button. Members who get a lot of unlikes are going to notice it for sure.
Just to be clear, we've only gotten as far as reorganizing a few things and rebuilding the database, so version 2.1 has not been installed yet. I don’t have an exact date yet when that will be available to us, but I hope to get that done either later this week or next.
The sub-forum reorganization is still ongoing, which includes working on some older forums which are hidden from public view. Most likely, those will end up being deleted in their entirety, so if you have posts in those forums it will affect your post statistics.
In short, you're going to continue to see some changes throughout the entire forum for the next few weeks as we work through these issues one at a time.