Slow roasted pork shoulder crackling advice

Morning fellow foodies, I want your advice or cooking techniques for slow roasting pork shoulder.

Now most recipes say high heat for first half hour to produce a crispy cracking skin, then to foil and slow roast for x hours.

When I do this obviously the crackling after x hours is then soggy and I have to then remove and grill to make it into crackling.

Should the recipes not bw flipped e.g. high heat after its ready to then make the crackling??

Thanks all.

bon appetit