I would assume you have a year at least.
If the focus shift with heat, then that was a very normal issue in the old days, and it can also still happen even in #1 grade systems, but much more rare now on the better systems.
But if the focus change with temperature so say its good on cold days and horrible on warm days, then you have a "live" lens that would need replacement, and that is not easy to do, and surely not something anybody should do if they have a warranty to lean on.
On the other hand if the focus had changed on a hot day, and stayed there, you could take the camera apart and refocus the lens ( turning it in its mount a few degrees ) but again, not something that should be done if there is a warranty to lean on.
If focus irregularities are on just parts of the image, then as jokiin said it is either a problem with the image sensor or the lens mount that encase it and hold the screw in lens itself.
Like looking thru a rifle scope, if things are not lined up correct ( your eye in relation to the scope ) you will not hit where the X is, so the lens mount of a deashcam could also tilt a little under heat stress, either from high outside temperatures or just prolonged use.
I would get things moving ASAP in regard to a repair / replacement / refund.