Jon Ralph and Michael Warner report there’s been a recommendation from the league's laws committee to introduce a 3-1 system with a limit of 80 rotations.
There was speculation that a 2-2 interchange system could be introduced, however a cap now seems most likely in what will be the second change in three years.
An early decision on the rule change would allow clubs to adjust their pre-season training programs.
Interchange rotations averaged 117 in 2010, 119 in 2011 and rose to 131 this season.
North coach Brad Scott predicted another change to the rule in April saying, "I think that it's inevitable that there will be a minor tweak to the way we do things at the moment."
Scott voiced concern over the initial change to a 3-1 system, arguing club doctors would be put under immense pressure to make calls on injured players’ ability to return to the field.
"You could imagine the pressure the doctors are under when a coach clearly wants to get a player back on the ground because you're one short. But the doctor has got to make the right call by the player," Scott said.
Earlier this year, AFL football operations general manager Adrian Anderson said the League would consider allowing a club to temporarily activate its substitute while its doctor assessed a player with suspected concussion.
One proposal was that club doctors would have 20 minutes to assess players for concussion and if a player was ruled fit to return to the field, his club would be allowed to put their substitute back on the bench and activate him again later in the game.
"We have to consider carefully the question of whether it could be abused," Anderson said.
It’s not known whether this concession will form part the changes to be announced.
It’s also been reported the league could move to tighten deliberate out-of-bounds, introduce faster ball-ups at stoppages and ban ruckmen from making contact with each other until the ball leaves the umpire's hand.
