He was planning to watch an advanced screening of Glasgow Girls, the BBC-commissioned musical drama about a group of his Drumchapel High pupils.
Several years ago, they helped to save a classmate, Agnesa Murselaj, a Roma from Kosovo, from deportation. She and her family had been detained in a dawn raid, and her father was placed in handcuffs.
"The original girls are coming to the house to watch the film," said Mr Girvan, a few hours before he welcomed them. "We'll have juice for them, even if some of them are now thinking along the lines of glasses of wine. We'll also have tissues available, as there will be a lot of tears."
Mr Girvan, 56, is the bilingual support teacher who encouraged the girls - Ewelina Siwak, Emma Clifford, Amal Azzudin, Roza Salih, Jennifer McCarron and Toni-Lee Henderson - in their principled fight against the Home Office in 2005.
In the new film, which BBC Three will screen on Tuesday, the teacher is played by Glasgow actor Gary Lewis.
"I just tried to make sure there were as many avenues open to them as possible to facilitate their struggle, and the cause they were fighting for," Mr Girvan said.
"My role as a teacher was to make sure they could participate in the process as fully as possible. And we managed that.
"The other thing, though, was that there was despair, and to turn that despair into something positive we went down that route too - because then we could say, at least we tried. If we sat back and thought, we can't do anything, hopelessness would have prevailed and people would have become desperate, not just the children, their families as well."
It helped that Mr Girvan was infuriated by the breach of child-protection laws, that children "could be snatched from right under your nose and you are not told what has happened to them."
Surely it was against what people would have thought were the laws of the land.
"Unfortunately, the UK Border Agency which carried out the dawn raid and its mindset were such that it couldn't take cognizance of that. Maybe they were. But they certainly ignored it.
"That is what made me angry: that children had arrived from war-torn countries, had settled for a long period of time. They had been through a trauma.
"And then this happened to them. It was almost as if they were subjected to a trauma created by the state in this country. I find that quite inhumane and wrong."
Asked whether the situation had improved on such deportations, he said: "It come and goes. There's a period where the Home Office does come back again and attempts to use its tried-and-tested tactics, of which much of Scottish civic society has been deeply critical.
"Neither the Home Office nor the Border Agency have changed its mindset.
"There are still dawn raids. There is still terrible destitution surrounding asylum-seekers in Glasgow. And in place of the old payment voucher system [for asylum seekers whose claims have been refused and are awaiting return to their own countries] there is now the Azure payment card.
"My concern is that the Agency has not been brought to account to justify its tactics. It keeps saying it will not comment on individual cases. It is not accountable. Its mindset, unfortunately, is incredibly hostile to the very people they are working with."
The Glasgow Girls have seen their campaign win awards and become the focus of cultural attention.
They featured in Lindsay Hill's award-winning Tales from the Edge documentaries for the BBC, which inspired Cora Bisset and David Greig's musical for the National Theatre of Scotland and the current drama-documentary, produced by Minnow Films.
"They are all doing well," says Mr Girvan.
l Jennifer is a childcare practitioner and volunteers as an Army Cadet instructor
l Roza is vice president for Diversity and Advocacy at the University of Strathclyde, having studied law and politics
l Ewelina Siwak is "a mother of two wonderful children"
l Agnesa is caring for the elderly
l Toni-Lee is about to do a nursing degree
l Emma is a producer on BBC Scotland and volunteers for a community news project
l and Amal, a community development facilitator at the Mental Health Foundation, is studying for her Masters in Human Rights and International politics.
Asked whether their successful campaign has impacted on the way they live their lives, Mr Girvan said: "Naturally. Yes. It has had a big impact on all of us.
"But it hasn't been easy. There was a stage version done, by the National Theatre of Scotland, and when we were discussing that, it brought back the trauma, the impact on our families.
"Similarly, with this film, I suppose we all have a fear about how it is going to impact on our families and on ourselves."
Mr Girvan met Gary Lewis and says he and the actor "have a similar outlook on a number of things, including social justice issues."
And he was happy that his former charges were being brought back together, even if it is just for a few hours.
"Some of them stopped me the other week and said they were looking forward to seeing the film but were apprehensive about its impact on our personal daily lives.
"But, in terms of people who can be looked up to, the girls have spoken at conferences, and continued to be inspiring to others.
"That's the thing I am most proud of: that they have developed into confident young women. I don't doubt they feel they are well-served for the rest of their lives through what they have gained through this process."
l Glasgow Girls BBC Three Tuesday, 10pm