NEW YORK (AP) — Hours after the players’ union voted Friday to accept an NFL proposal on drug policy changes that included HGH testing, the league says it is not a done deal.

Player representatives to the union also voted for changes to marijuana testing, classification for amphetamines, punishment for driving under the influence, and neutral arbitration on appeals.

But NFL spokesman Greg Aiello said in an email to The Associated Press: “There are unresolved issues. More negotiation ahead.”

Aiello did not specify which issues are not resolved, but called them “significant.”

Testing for human growth hormone was originally agreed upon in 2011, but the players have balked at the science in the testing and the appeals process for positive tests. If the proposal they voted on Friday is put into action, testing would begin for this season.