Well, the refueling time is a kind of cooldown timer now, isn’t it? 
It’s one or the other I guess 
@ICEgamer1705 Also to add to this
It technically does i think because the route determines how much fuel your plane comes back with. I found that of my A320s at PRG, the two that i send for connections to INN and BRI always come back with a basically full fuel tank, maybe a few seconds of refuel required.
Though im not sure how visible this difference is on L and X planes
