The key section of this story is >The board cannot impose fines or direct punishments against Apple for its violations. Which makes me wonder why they spent two years working on this investigation.
They have a lot more power than you might think from that quote. https://en.wikipedia.org/wiki/National_Labor_Relations_Board... They can now try Apple in an administrative court, with an 'administrative judge' selected by the agency, then get a (normal) Article 3 court to rubber-stamp their 'order'.
edit: further investigation has indicated that it's immigration law which deviates from usual practice of administrative law, which would potentially expect an automatic stay in a context like this.