John Curtain Liberation Question

[Ashmantious]

I'm in a game where one Civ (who I was friendly with) was eliminated because it lost all of its cities to loyalty, they flipped to free and no other civ could flip them. I just got Diggers and I am contemplating sending my digger and artillery army out on a "grand tour of liberation". From what I understand liberating multiple cities doesn't stack, it just resets the counter on the production boost. My thought is to free a city every 20 turns (this should finish the game for me as there are over 1/2 cities to liberate. Is my assumption on the "clock resetting" instead of the boost stacking correct? Is there any counter you can look at in-game to tell you how many turns you have left or do you just have to keep an eye on your cities' production?

 

[Equilin]

It is correct indeed. And the easier way than to check your cities every turn is to write down the turn you did it and then count; there are no indicators in game aside from the city panel.