I know that this rule has probably been posted already... From the NFL Rulebook (Rule 5 Section 3):
Section 3 Changes in Position
REPORTING CHANGE OF POSITION
Article 1 An offensive player wearing the number of an ineligible pass receiver (50–79 and 90–99) is permitted to line up in
the position of an eligible pass receiver (1–49 and 80–89), and an offensive player wearing the number of an eligible pass
receiver is permitted to line up in the position of an ineligible pass receiver, provided that he immediately reports the
change in his eligibility status to the Referee, who will inform the defensive team.
He must participate in such eligible or ineligible position as long as he is continuously in the game, but prior to each play he
must again report his status to the Referee, who will inform the defensive team. The game clock shall not be stopped, and
the ball shall not be put in play until the Referee takes his normal position.
In the bolded part of the rule, do we know if the Patriots players who reported as ineligible stayed ineligible until they were off of the field for one legal play? For example: A Patriots RB reports as ineligible for play 1 from scrimmage. That RB MUST be ineligible until he comes off of the field and every play MUST inform the referee every play that he is ineligible. This would be an easy thing for an official to overlook.