We had a 2005 astra with the same engine in today with the exact same code pulled using our kts, seems as though the symptoms are the same aswell.
If we went over 3k rpm and then backed off the car would put the eml light on and go into 'limpmode' immediately, if we drove steady it was fine.
From watching live data on our road test it looked as if the EGR valve was sticking but we didnt look any deeper into it.