This one is easy to reproduce:

-Play a game

-Select the Persians during the Classical Era

-Build a military unit

-Use the Expansionist ability and target an outpost


It takes a few turns to steal an outpost that way and there's a cooldown of 10 turns to re-use the ability.

But you cannot cancel the process once it's started. I went as far as moving the unit out of the outpost, back in my territory and then disband it. The process was still going but backwards.

It showing -29 turns to completion now:

20210821000252_1.jpg


We should be able to cancel the process and potentially start it somewhere else without waiting for the cooldown.