2 updates in 2 days! I'll be getting a job offer from Studio Wildcard any day now.
After months of dodging meetings and saying "let's circle back to this", a member of the mayors union finally cornered you and made it clear mayors are no longer going to work for free. Starve a city of gold and any mayors in it may leave your employment!
When a city has 0 gold, approximately every hour one of your mayors will revolt and leave your city
The exact time at which the revolt happens is randomised, to reduce an exploit where a clever player could figure out when the desertion period is due and obtain a small amount of gold just to cover that period. Revolt happens between every 40 and 80 minutes to a city with no gold in it
Mayors lost to revolt will be retrievable from the "Retrieve mayors" screen, the same way they are when lost in a conquest, but you will have to pay to retrieve them.
Alongside this update, it's been decided that mayor wages - particularly for high level mayors - was far too harsh, so this has been reduced, as has the retrieval cost for rehiring lost mayors.
It's been highlighted that valleys other than gold mines are of little use to bigger players, so a percentage buff of your total resources is now granted to a city when you conquer a valley, alongside the usual flat resource production.