BROSSARD, Que. — The Montreal Canadiens’ dressing room is not arranged by accident; which player is sitting next to which player matters and is well-thought-out.Not every single locker assignment has a greater significance, but there is usually some sort of meaning that can be drawn from it. And rarely have dressing room locker assignments seemed more significant than on Monday, as the Canadiens players were cleaning out those lockers to head their separate ways this summer after a successful season that saw one of the youngest teams in the NHL put up 106 points in the regular season and reach the Eastern Conference final.As captain, Nick Suzuki’s locker is at the centre of one side of the room. To his right, there is the locker of rookie Ivan Demidov, a big part of the team’s future. And to his left, there is the locker of Brendan Gallagher, who informed the world Monday that he will soon be a part of the team’s past.Past, present and future combine in the Canadiens’ locker room. (Arpon Basu / The Athletic)Gallagher’s placement in that dressing room underlined his importance as a leadership support system for Suzuki, who was officially named captain a month after his 23rd birthday. Nearly four years later, Suzuki is now a seasoned captain, someone his teammates look up to, someone who makes sure everyone feels involved.At first, Suzuki needed Gallagher’s help in that area. He no longer does.Demidov’s placement underlined how important his development is to the team’s success, and giving him direct access to Suzuki in that room helped ensure that proper development.And in a sense, those three lockers being placed next to each other is a perfect representation of the challenge Canadiens president of hockey operations Jeff Gorton and general manager Kent Hughes face while tackling this next phase of their rebuild.There is a layer of young talent represented by Demidov, but also including Lane Hutson, Juraj Slafkovský and talent that has yet to arrive in Montreal like David Reinbacher, Michael Hage and Alexander Zharovsky. There is the core talent of young veterans like Suzuki, Cole Caufield, Noah Dobson, Kaiden Guhle and Alex Newhook — all roughly the same age, all entering varying stages of their prime years, all expecting to build on this playoff run next year. And there is the older veteran layer represented by Gallagher, 34: a layer that is very necessary to the success of any young team, but one also susceptible to being pushed out by the continued growth of that young team.After amassing all the young talent that created this difficult situation, Gallagher becomes the latest victim of a natural cycle of renewal any rebuilding team strives for. Another element of that renewal is represented by the player on the other side of Suzuki’s locker, with Demidov eligible for a contract extension on July 1 and saying Monday he hopes to sign a long-term extension with the Canadiens as soon as possible, with Hughes confirming the Canadiens are hoping for the same thing.Gallagher broke down in tears as he delivered the news to reporters that he had essentially requested a trade and had played his final game for the Canadiens after 14 years of representing the franchise and his adopted home city with pride.It might be a natural cycle, but that doesn’t make it any easier.“I guess it goes both ways,” said Gallagher, who has a full no-movement clause on a contract with one year remaining at a $6.5 million AAV. “It is obviously my decision, but you’re kind of forced into it. I would love to stay here and love to be a part of this group. But for me, you have to give yourself an opportunity to contribute. Just the situation, where it is now, it’s not going to change, right?”In fact, it will change.The bar to be able to play for the Canadiens will only continue to rise, and while Gallagher was the most painful departure Monday, there will be others — including goaltender Sam Montembeault and forward Patrik Laine — who probably also had their final media availability as members of the Canadiens on Monday.But what makes this phase of the Canadiens rebuild particularly interesting is the extent to which those departures might not solely be reserved for older veterans. They are at a point where specific holes will need to be filled to continue pushing this team toward becoming a legitimate Stanley Cup contender, most notably a centre for the second line and a right-shot defenceman for their top four.The Canadiens have candidates within their prospect pool that can fill each of those holes: defenceman David Reinbacher, the No. 5 pick in the 2023 draft, and 2024 first-round pick Michael Hage chief among them. But those holes will likely need to be filled before either Reinbacher or Hage are ready to fill them, and there is no guarantee they ever will be.Hughes has often said he does not want to acquire players and contracts that will block the organization’s youth from emerging. That might be about to change.“I think that’s inevitable for us,” Hughes said. “We’re certainly closer to being in a position where we would accept that scenario than when we first got here …where we would never have accepted it. So we’ve got to continue to make decisions here as we go … If we make a decision that blocks a path for a certain type of player, then we have to make an evaluation as to what we do. Does that mean that player becomes available to trade or do something else?“I think in theory we’re at a point where we might make a decision on something that makes it harder for another player to reach his potential.”Gorton and Hughes have been aggressive in every offseason. But the status of that middle group of talent — the Suzuki tier — and how close that tier is to their peak will mean doing things to fully optimize that peak, while also allowing the Demidov-Hutson-Slafkovský tier to reach its peak as well. And this is where the management of Reinbacher in particular becomes somewhat difficult.The Canadiens were looking at right-shot defencemen at the trade deadline, among other things, and that in and of itself was a sign Gorton and Hughes feel that is an important element this team is missing, at least in part because lacking that player forces Hutson to play on his weak side.Can Reinbacher be that player despite all the injuries that have been obstacles to his development, and if so, will he be ready in time to fully optimize the Suzuki tier’s prime years?“I think there’s still a path for David to be a big part of us, going forward,” Gorton said. “We’re just trying to get through those interruptions. But before he got hurt the last time, his level was pretty high and pretty consistent; we knew what we were getting every night. We still think the future’s pretty bright with David. Unfortunately it’s just been injuries he’s dealt with. Hopefully he’s through that and in September, October, we’re talking about something totally different.”The key word there is “hopefully.”There is a longstanding doctrine in hockey that hope plays do not work, and while player projection is inherently hopeful and there are rarely guarantees, the uncertainty that comes with the word “hopefully” is what this management team must now guard against.Hutson, Demidov and Slafkovský — despite some difficulties for each of them in the playoffs — represent relatively sure things for the Canadiens, and once Demidov is signed long-term, they will all be locked in through their prime years. But in terms of filling those two holes at centre and right defence — there are other holes, those are just the biggest ones — the Canadiens have reached a point where they are on the clock, to some extent.To be clear, the Canadiens are just opening their contention window, so it is not as though Gorton and Hughes are under the gun. But contention windows can be very fragile, even the ones that are wide open.“When Colorado was eliminated, I sent a text to (Avalanche general manager) Chris McFarland,” Hughes said. “His reply was short, but he said it’s a trophy that is so hard to win. I think what we see is there are a lot of positives to take out of this year, both in terms of the team and in terms of the individual efforts as well.”What Gorton and Hughes are tasked with is something their coach, Martin St. Louis talks about constantly. They are in charge of increasing the odds of the Canadiens winning, knowing nothing is guaranteed.The fact the Canadiens lasted one game longer than the powerhouse Avalanche shows the extent to which they have moved this project along considerably, but the fact the Canadiens were so thoroughly dispatched by the Carolina Hurricanes shows how far they are from the ultimate goal.And this transition, from a team coming out of a rebuild to one being a true contender for the Stanley Cup, is easily the most delicate phase of this project.The Canadiens tried to add the pieces Gorton and Hughes felt were missing at the trade deadline, lacking the time or the cooperation necessary to close what Hughes described on deadline day as a “significant deal.” He said that day and repeated Monday that it is a deal that can still be revisited now.“Our point of view is not necessarily different now than it was at the deadline,” Hughes said. “It’s not as if anything surprised us.”That point of view was central to that deadline day mystery trade, whatever it was. But Hughes also mentioned that the parameters have changed now.“What will be available in June,” he said, “won’t necessarily be the same as what was available in March.”Gorton and Hughes have done some of their best work in June. Perhaps this June will be no different, but the approach might just change, because priorities have clearly changed.There are young, promising players in the Canadiens’ system who might never get a chance to play for Montreal because the competition to play here is so fierce, but who nonetheless could be ready to play somewhere in the NHL somewhere.The Canadiens have those young players as ammunition, they have nearly all of their draft picks this year and next as ammunition, and they have entered a phase where just about anything seems to be on the table for the right player to fill the right hole in a rebuild that is verging on completion, but requires a few more specific, targeted steps to get it across the finish line.“We will continue to follow the plan,” Hughes said. “But the plan is always changing.”This trip to the conference finals accomplished a lot for the Canadiens. It gave their young core a ton of playoff experience. It gave their young coaching staff an opportunity to learn and grow. It gave management a wealth of information on how their players performed in a playoff environment and what type of players they need to complement what they already have.But the biggest thing might very well be that no single event has changed this administration’s plan more than what happened this spring. It will be fascinating to see just how extensively that plan has changed.