I built some fence using treated 4x4 posts. The 15 year old posts are fine. some of the ten year old posts are rotted off about 6-8" down all the way. I doubt I still have receipts but I might. Home depot has never had labels saying if it is ground contact or not. Logically since they do not say it should be implied fence posts are ground contact treated.
Any hope of getting replacements for free. I know they will not pay for my labor
Bill D.