At an altitude close the the limit, a turn will increase the effects, the flow over the faster (outside of turn) wing going more supersonic with more turbulence from the shock wave, and the flow over the slower (inner) wing slowing down. The machine is literally going both too fast and too slow at the same time - and it is only going to come down.
[dredging memory] Is this the reason why Concorde has to fly dead straight in high speed cruise? Because, if she turns even slightly, then all of these forces will leap out at her?