Ok, that kinda did it, the HTML disappeared. Now I have posts with exposed UBB tags and all the breaks between paragraphs went poof. As a followup, I tried this:

Code
update ubbt_POSTS set POST_MARKUP_TYPE = "both" where POST_ID < 304806

That didn't seem to change much.

I do have a backup prior to the rebuild of the posts. Does it renumber posts at all, or should I be safe to just restore the posts below X ID?