GT Radial Adventuro AT3

Adventuro At3 – While driving down the road at 50kph I received a giant split in my tyre which are 6000ks old, when taking it back to the store of purchase it had to be reviewed by the gt radial rep which took a week, once he looked at it he went away and 24hrs laterhe claims it was an impact fracture... if it truly was then why did it take 24hrs for him to make a decision and why is he offering a replacement at cost price? It is poor service by them and I won't be going back to this company for more... I have travelled Simpson desert and more on the same model tyre and never had a problem... sometimes a product has a fault and sometimes a company must wear such a problem...