It's not only 1 month, he was bad all year long except the first 5 games with MSL and it's not like If he was 30 and a bad year can happen. Usually Dmen are starting to slow down at Petry age so GM will clearly consider that. Just look at the return that Dmen with term and at Petry age usually get.
The thing is most people forget how good he's been for the last 3-4 years. I certainly get he's older, but it's not like he's lost his mobility, which is what normally happens to older players. Previous to this year, he would have got a haul in a trade as was deservedly in consideration for the Norris trophy.
People see how old he is and his stats and think that play must be due to age and he's done, but I don't think that's the situation at all. IMO it's a case of starting the season injured due to the run last year, being away from his family, and being a part of the worst team in the league which completely lost its identity.
I wouldn't be surprised at all to see him bounce back next year to his statistical norms, either on the Habs or another team. I don't think management is going to give him away, and I don't think Jeff is going to force their hand, so it's a case of offering something decent or he's not going anywhere. And I think that is fine with Montreal's management.