Rather than use the griller element to rescue the crackling, I cook pork roasts using the top griller element/fan on combination. It works a treat.
The trick is to start the roast from a cold oven so the grill element can work its magic immediately. A bit of trial and error is needed to work out the best shelf to put it on so it crackles but doesn't burn. I set the temperature for 180 deg C. Also, by putting the meat in one of those 'V'-shaped wire racks that have adjustable sides, it's possible to move it to ensure all the skin crackles.
After all the crackling is perfecto, I just flick the oven selector over to conventional fan-forced at the same temperature for cooking, by the meat thermometer, to complete. Works every time, which is not my experience of the 230 deg first stage method.
Just sit back, open the pinot noir and wait for the fight over the crackling

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