1. The Packers will have double the cap hit for next year totaling $30 mil if they trade AR before June, but if they wait until June then the cap hit is spread over 2 years.
That could be a reason to delay the official transaction.
2. The trade could involve conditional draft picks which are dependent on AR's performance such as making the play offs, and whether he continues playing for 2 years or not. Conditional draft picks were used when the Packers traded Brett Favre to the Jets.
IMO it's basically a done deal unless AR changes his mind about collecting his huge sweetheart of a deal payday.