Flat spotting is common with bias-ply tires, even just being parked over night.
You run Radial tires.....not known to flat spot. Some will in the larger mud terrain tires though.
I park trucks for 3 months over the winter and never had an issue with flat spotting. My old 38" PJs would flatspot though.
As was mentioned when you start to drive you know if you have any flat spotting or not (bumpy ride). Over the first few miles the tires start to heat up and get back to being round again.
Flatspotting doesn't damage the tire really, just annoying....