When I use autoresolve and one of my champions decide to use mana, it is not instantly removed from the global resource bar.
In this scenario, I had 62 mana. I was about to cast Corruption on a shard. I used auto-resolve just before with a fire champion that used up a lot of mana. The bar still said 62 mana, but I was unable to cast corruption. When hovering over the resource, it said I had only 17. When I pressed end turn, the mana number was updated.