I noticed a Pattern in the Civ VI Change Depots on SteamDB: many of them contain the Base Game, XP1, XP2, DLC1 (Vikings), DLC2 (Poland) and DLC 5 (Nubia), but no other DLCs. I didn't dig deeper, so don't take this as reliable/proof.
Does this mean that we're getting, for the smaller DLCs, balance/polish for Norway, Poland and Nubia only? And not for Macedonia, Persia, Australia, Aztec, Indonesia and Khmer? The Devs said that it's going to be only 2/3 of the Civs/Leaders, but that's just 1/3 of the smaller DLCs Civs. So perhaps Most of the Base Game Civs and RnF Civs will get rebalanced/polished.