Matthews will leave Glasgow Warriors at the end of the season to join Montauban in France, bringing the curtain down on a hugely impactful spell that included a pivotal role in the club's famous 2024 URC title win, where he finished as top try scorer.
For Stephen, the timing underlines a changing of the guard at hooker. Stephen has been given increasing opportunities and is now firmly in the mix as a leading back-up option to Gregor Hiddleton. And the 20-year-old has been quick to acknowledge just how important Matthews has been in his development.
Asked about the departing hooker, Stephen said: "Oh, Johnny's great. He's pretty good at giving any feedback on stuff you might get yourself worked up about because it's easy to get in your own head.
"Johnny's obviously experienced with... he's got 100 games for the club, so he's experienced with being able to deal with different emotions and different circumstances that he's probably been through. So, yeah, he's a good old head."
Matthews' exit could open the door for Stephen next season - but the Scotland U20 international is not taking anything for granted, given the depth still at the club.
Asked if the departure created an opportunity, Stephen said: "Yeah, I'd definitely say so, but at the start of the season I was looking at the hooker depth chart and thinking, oh, there's quite a big task ahead because there's something like seven hookers at the club at the moment.
"I still think there'd be six left, so there'd still be a lot of competition apart from Gregor, so I'll have to earn my spot, definitely."
On his development over the last year and his first pro deal, Stephen said: "I came in last summer and got offered an academy contract for two years, so I'm pretty happy to be starting my pro one now, so yeah, first one ever.
"I think I've just enjoyed training here, and I think that's helped me to push on and play more games this season. At the start of the season I probably had a goal of playing just a couple of games, so I'm pretty grateful to be in the position where I've played ten or maybe a bit more than that. I've enjoyed it so far, so I think that's a massive part of it."