It sounds as if, if there is anything before new year, it'll be quite small. They are certainly doing expectation management on the civ discord.
It's a bit of a shame, I've had extremely limited desire to play Civ7 this month. But the devs deseeve a holiday.
My hope is that the 2nd half of tides isn't too gimmicky. Tonga and pirates were just too themed around a single gimmick for me, and don't really make me want to do multiple games with them. .. Or even a single one with the pirates. That said, with Iceland and Ottomans appearing in later eras it'a gonna be an uphill struggle for them to be rewarding from the outset.