Sort of an aside. With age related failures (like tread separating from casing) the front tire normally exhibits the symptoms simply because the rear tire wears out much quicker. I've had to toss "unworn" but cracked front tires after a number of years while going through a few tires in the rear.

Now I try to rotate the tires so when I wear out a rear I move the front to the rear and mount the new tire to the front.

I did try "rotating" the tires but I didn't like looking down at a more-worn front tire. Personally I like seeing a proper profile front tire since the front tire is significantly more important safety-wise than the rear. So no squared off tread, no thin areas of tread, etc.