Where does it say that? Might want to reread what was actually said. Where does that say December 2019 - January 2020?
If you want to get technical. None of that part was a direct quote from Holly. So who knows how much reading into it the writer did.
I don't think they will merge Agnarr into another server either, but your reasoning kind of fails if they wait until Omens of War or something to do the merge.
I can't find anything that says Dec-Jan, it might have been said in one of "The Everquest Show" episodes at the time. I don't recall. There was much discussion about it at the time, the usual merge controversy. Point is, there was a tech issue exacerbating the delay, and I'm betting still is. Server merges are about like Fan Faire at this point. They're gonna keep talking a good game, but as the days keep ticking away............. I could be mistaken. I'm not always right, I just have a decent track record.