If you are a San Jose Shark — or know one — make certain that your cell phone is turned on at all times over the next few months. Stuff is going to happen.

And by “stuff,” that means potential trades or releases of anyone on the team over 25 or 26 years old.

And, yes, that means Joe Thornton and/or Patrick Marleau and/or Antti Niemi and/or Brad Stuart and/or many other customer favorites could soon be leaving town.

“When you enter into this phase, no option is off the table,” said Shark general manager Doug Wilson during a Thursday conference call.

Of course, it’s one thing to say something and another to do it.

But the more I hear from National Hockey League voices I trust, the more I believe it is unlikely that both Thornton and Marleau–the core of the Sharks’ core—will be back in teal uniforms for the 2014-15 season.

After franchise owner Hasso Plattner said this week that Wilson and head coach Todd McLellan will be returning, Thursday was the first chance for Wilson to publicly set the stakes in the ground for what’s ahead in this Summer of Shame following the playoff collapse against the Los Angeles Kings.

And while not mentioning Thornton and Marleau specifically, Wilson said this while responding to a question about which players most disappointed him during the playoff collapse against Los Angeles: “When you see some of the things we’re going to do, you’ll have the answer.”

Wilson also said that the offseason moves would be “more drastic than putting a Band-Aid on it” and that his goal moving ahead for the Sharks is to mold a “harder, younger, more aggressive team that will stay with it.”

What does that tell you? It tells me that Wilson thinks that his team, as currently constituted, is not hard enough or young enough or aggressive enough.

Wilson also acknowledged that as bad as this season’s exit was–blowing a 3-0 series lead to the Kings and being eliminated in seven games—it was merely connected to a trend. The Sharks, for all of their regular season success, have now lost four of their last five playoff series going back to the Western Conference finals defeat by Vancouver in 2011.

In the past, while making minor tweaks, Wilson has defended the Sharks’ blueprint of “refresh and reset.” But on Thursday, he used words he has not spoken before in relation to the team. He used the word “rebuilding” in terms of the months ahead. He used the word “cultural” in terms of why the Sharks have come up short so often.

Folks, you don’t have to reading between the blue lines to read what this all means. Thornton and Marleau will be 35 before the start of next season. Stuart will be 35 in November. Niemi will be 31 in August. It will be interesting to see where Joe Pavelski, who turns 30 in July, fits into the package. Wilson affirmed that many of the veterans do have trade-restriction clauses in their current contracts, including the three-year extensions signed by Thornton and Marleau last winter, but said there are “flexibilities and windows” in all the deals.

Meanwhile, to kick off the Summer of Shame, Wilson made a couple of announcements that were expected and one that wasn’t.

The two expected pieces of news: Dan Boyle, the veteran defenseman, will not be returning to the roster when he becomes a free agent in a few weeks. Neither will 33-year-old forward Marty Havlat, whose contract has one more season to run. Wilson intends to either have owner Hasso Plattner buy out Havlat’s $5 million salary for 2014-15 under the NHL’s amnesty provision or will try to obtain as much (or as little) in trade as possible for the oft-sidelined 33-year-old forward who was probably most famous here for once injuring himself while climbing over the boards on a line change.

The unexpected news: Brent Burns, who came to the Sharks as a defenseman but was shifted to a forward position in the spring of 2013 and stayed there this season, will be returning to his former spot on the blue line.

Wilson said he decided to keep McLellan and his staff because (A) they have 12 combined Stanley Cups on their resumes and (B) he has been pleased with the way McLellan and assistants have developed many of the younger Shark players.

However, Wilson added that the younger players don’t get a free skate from responsibility in the Kings’ collapse.

“I expect those young players to take this as a kick in the ass as something that will never happen again,” Wilson said.

Will fans of the Sharks be able to handle a major shakeup like this, perhaps taking a step backward to take a few steps forward? If they are as smart as I think they are, and if they have been paying attention over the past 23 years, they should. That is, as long as the plan shows signs of working — maybe not with wins or losses on the scoreboard but with style of play.

And there’s no reason to think that by going younger, the Sharks still can’t make the playoffs. The Sharks’ younger core includes such players such as Logan Couture and Tomas Hertl and Tommy Wingels. Defensive prospect Mirco Mueller is supposed to make the varsity next season and have an impact.

Those guys may be the only Sharks players who don’t have to worry about a phone ring and a trade between now and September. But they had better be prepared to meet a bunch of new teammates. Wilson sounds serious. I think he is. Stuff is going to happen.

Read Mark Purdy’s blog at blogs.mercurynews.com/purdy. Contact him at mpurdy@mercurynews.com. Follow him on Twitter at twitter.com/MercPurdy.