This article explains it better than I can
Article 'Guide to Assisted Hatching for All Poultry' https://www.backyardchickens.com/articles/guide-to-assisted-hatching-for-all-poultry.72886/
If it's been over 24 hours since he has internally pipped, I'd be making a safety hole. Even if he hasn't internally pipped, I'd *think* about opening a safety hole
The longer you wait, the more fertility is going to drop. That being said, after so many days in the mail, they could be all kinds of shaken up, so I'd still do 24 hours of pointy side down. I'd actually consider doing more. This is a tough situation, I'm so sorry :hugs
What's the humidity reading now? Today is day 21, right?
Please read this fantastic article about assisted hatching, if it comes down to that
Article 'Guide to Assisted Hatching for All Poultry' https://www.backyardchickens.com/articles/guide-to-assisted-hatching-for-all-poultry.72886/