April 15. Tax day, and the day upon which Vikings running back Adrian Peterson is eligible for his NFL reinstatement.

The former is a definite. The latter is anything but, according to NFL spokesman Greg Aiello, who sent this e-mail reminder of Peterson’s vague timetable when asked Tuesday if the league would be removing the former NFL MVP from the commissioner’s exempt list Wednesday:

“Here is what we said regarding April 15 when we announced his suspension [last fall],” Aiello wrote. “Adrian Peterson of the Minnesota Vikings was notified today that he has been suspended without pay for at least the remainder of the 2014 NFL season, and will not be considered for reinstatement before April 15, for violating the NFL Personal Conduct Policy in an incident of abusive discipline that he inflicted on his four-year-old son last May. … In order to assess [Peterson’s] progress going forward, [NFL Commissioner Roger Goodell] will establish periodic reviews, the first of which will be on or about April 15, 2015.”

As part of his decisionmaking process, Goodell summoned Peterson to NFL headquarters for a meeting last week. It lasted three hours, but neither the league nor Peterson has commented on the meeting or provided a more specific timetable for the running back’s reinstatement.

Unless Goodell feels Peterson has not met the terms of his suspension, which included the requirement that he speak with a league-assigned psychiatrist to design a counseling and therapy program, the expectation is that Peterson will be reinstated.

Peterson has been moved from the commissioner’s exempt list to the suspended list and back during the lengthy ordeal that began to unfold the Friday after the 2014 season opener. The Vikings have stated publicly numerous times that they want him back and have no intentions of parting ways despite agent Ben Dogra’s comments that his client would be better off playing elsewhere.

Assuming Peterson is reinstated beforehand, his first mandatory appearance would be during the team’s June 16-18 minicamp at Winter Park.