Sorry to say but definitely 'jack stall'. The manoeuvre was run low level toward the crowd line, 150kts to 90 degree nose up, wait for zero climb, 180 pitch down to vertical with a rapid 360 roll once in the vertical.
I was flicked out of that manoeuvre with an associated master caution! As stated, not any fault of the aircraft, it was extremely gusty and my handling was probably a bit off.