They could not have been more wrong. The news was that he had just been called up to join the Scotland squad preparing for the final Test of their summer tour in South Africa. Better still, with only four back-row men in the party, he was guaranteed a place in the match-day 23 and almost certain to get his debut cap, hopefully in the starting XV.
"I rang on Skype, and was chatting to my mum because my dad was still at work and I wanted to wait for them to be together," Holmes said as he and his new international team-mates got down to work to prepare for the Test in Port Elizabeth.
"He thought something was wrong because I was waiting for him but when I did break the news he was really happy, ecstatic, he had tears in his eyes. It's an eight-hour drive up here from Cape Town so they are coming up and making a weekend of it. There may be a few of my friends too, I don't know yet. It has all happened so quickly."
Which is certainly true. On Wednesday last week, he was going through a particularly tough pre-season training session at Glasgow after failing to make the original Scotland selection. Then he got a phone call from Gavin Scott, the Scotland team manager, to invite him to join the squad for the final Test of the team's summer tour.
Three days later he was on his way, arriving the following day and being joined by the rest of the party, which had made its way from Argentina, the day after that.
Born in Johannesburg, Holmes' family now live in Cape Town and he played most of his rugby in South Africa, for Western Province in the Currie Cup and a couple of games for the Stormers in Super Rugby. However, he insists that he is not a glory-hunting bandwagon jumper. International rugby was the goal but with his Peebles-born father, Steven, encouraging him, he has had his sights set on Scotland pretty much since he turned professional.
"When I decided to make it my profession, we always spoke about Scotland," he said. "When I moved to Scotland, this was the goal, though I did not know it was going to come as quickly as this. The fact that it has is great but getting capped for Scotland was always something I wanted to achieve. I've got an A cap, which was was a great achievement in my first season. I learned a lot from that and about what it takes to stay involved and make a name for yourself."
The A cap came in the pouring rain and mud of a cold Scotstoun night in February, conditions that could not me more different to those Holmes grew up playing, which are exactly what the Scots can expect on Saturday.
"I like to think the conditions will suit me better," Holmes said. "I grew up playing in these conditions with a dry ball and a faster game, so I am quite excited to get a shot at Test rugby in conditions I know. I hope the weather sticks and I get a chance to get on the park and run about.
"Obviously there is a nervousness but as a kid this is the stuff you dream of, it does not get any better than this. I can't wait. I think my experience of playing here will help. I've played with a few of the players and against most of the Springbok side in the Currie Cup.
"Every team wants to go out and put in that perfect game, that's why we are here, that's why we play rugby. If we do that, the result will take care of itself. The last time Scotland were here it was tight, we made it tough, and that is what we are aiming to do again," Holmes added.
"I have been chatting to lots of the boys and getting the vibe out of the camp. It seems that it has been a very positive tour even if we have not played at our best yet. That is the aim this weekend."