baseta26 I had a similar experience to DaveH with my Grapil, broke exactly the same way. My bike shop were excellent with dealing with it, and I wrote a stern email pointing out it has happened to multiple frames all at the same point and that it was clearly a manufacturing fault and I had lost all faith in the design as a whole, and why pull the bike, mid way through its year cycle if it wasnt a serious issue…Shame as I loved the bike, the geometry was ace.
The re-designed rear could be fine, Nukeproof megas suffered a similar problem on the 1st versions but they quickly sorted it and moved on. Id be asking for a new frame though..