Four months ago, Teacher Tapp data revealed that half of teachers had answered emails during the Christmas holidays. This sounds innocuous enough, but the figures caused a bit of a battle on social media.

Email answerers were at pains to explain it wasn’t necessary for other people to answer their emails out-of-hours or reply to 11pm mailing binges. The emailers just preferred responding as things came in so they weren’t overwhelmed on their first day back at work. Or they liked to email late at night once their kids or other half were out of the way.

Non-emailers were not placated. “Constant emails lead to a 24/7 culture and it’s unsustainable,” one person tweeted.

“It’s like everyone is trying to get the monkeys off their back before the return of term, but they do it by passing the monkeys to other people. And then I have to worry about the monkeys they’ve handed over to me,” another confided.

If you wouldn’t phone somebody about the issue, then you probably don’t need to send an urgent email either

I’ve presented this finding several times to audiences of headteachers since then. Each time, the same frosty divide goes up in the room. Half are desperate to point out they like managing their work by doing emails at night, and that it’s very important for their wellbeing, work-life balance and so on. The other half say their wellbeing and work-life balance would be better if everyone agreed to stop emailing after a certain time.

At one point, when presenting to a room of heads at an academy trust, the chief executive suggested he experiment, one weekend, with switching everyone’s emails off at 9pm on a Friday night and switching them back on at 6am on Monday. One head immediately blurted “no” across the room. Her fear at taking away out-of-office access was palpable.

Yet, the more I talk about this issue with people the more I think schools need to find a solution.

One problem of teaching is that it’s a performance. For up to six hours per day, teachers are on stage. They must give their undivided attention to groups of 30-plus needy pupils. Then we add break duties, extracurricular clubs, department meetings, lesson planning and book marking. Each of these requires serious powers of concentration too.

It’s therefore no wonder many teachers (and leaders) feel they can only answer emails in evenings, when all of these demands are gone. But this means they never get any time off stage. And while that level of control and work can feel joyful – because productivity feels good – it is also bad for us. Gradually it leads to people feeling out of control and resentful.

At this point I usually get cornered by people insistent on two points. One, that out-of-office emails are important for working parents who have to leave schools early to pick up their children.

Two, that every other sector is struggling with this same form of digital creep and teachers are no different to anyone else.

Let me take this latter point first. Teachers are different because they are the sector I’m interested in. The bakers, and lawyers, and candlestick-makers can fight their own battles and maybe theirs will involve everyone sucking up a 24-7 work culture. But that doesn’t mean teachers should.

On the parenting point, I concede that childcare affects the hours people are available, but I don’t think family life is helped by parents watching their phone notifications all evening.

Plus, I notice that no one is ever mad about people writing emails in the evenings – the issue is sending them.

Technologies such as boomerang on Gmail or delay send on Outlook enable people to write emails whenever but to send them later, meaning people only receive work emails within work hours, which changes expectations about responses.

They can be overridden, in emergencies, but a good rule of thumb is that if you wouldn’t phone somebody about the issue, then you probably don’t need to send an urgent email either.

Will this save us from a teacher shortage and the workload crisis? Not by itself. But at the very least it’s worth having a conversation with colleagues.

Do you have an out-of-office email policy? And if not, why not? You may be surprised at the answers.

Laura McInerney is Contributing Editor of Schools Week