The real problem here with tires is not the concrete. It's with the sitting.
Tires can flatspot. The more load (less inflation), and the longer it sits, the worse the flatspotting. I've heard of tires flatspotting in 3 months.
But the vehicle has sat for a year, so it undoubtedly has flatspots.
What to do?
First, move the vehicle forward or backward a half a tire revolution (4 feet?). That would put another flatspot 180° out of phase, which is better because the suspension reacts to a single flatspot worse than 2 flatspots.
Or jack it put and rotate the tires 1/2 turn.
Another would be to overinflate the tires - say 20 psi. No!!, the tire will not explode (unless it is damaged, but then it was going to explode sometime later anyway!)