A player who begins the regular season on the PUP list must sit out his team's first six games.
After that point, a team has three weeks to start having the player practice; once the player begins practicing, the team has another three weeks to put the player on the active roster.
If the player is not activated by that time, or if he does not begin practicing within that three week window, he must remain on the PUP list for the remainder of the season