Out of interest, why are you trying to leave a career in IT? I have worked as a school administrator in primary and secondary schools. Sorry to be negative - you may really need this new job - but the pay is peanuts and expectations of you are unreal; think, juggling about 5 balls at a time. I’m someone who takes great pride in doing a good job but life in school is frenetic; you have to do everything at pace and there is never a point you reach where everything is done. You have to constantly prioritise.
I would suggest you come out of the interview being clear of what your job will involve. If you get the job, have strict boundaries in place. I like to be helpful but I made a rod for my own back and took on more and more, certainly work/decision-making that was above my pay grade (also stepping in as a midday supervisor as about 50% of the time we were short staffed).
Will the job involve first aid? That was an aspect I found tough in primary, making the right call as in loco parentis. Every day there were bumps to the head and falls and, although there were many other first aiders, it was down to me whether I involved parents or rang an ambulance etc. I got flack from some staff for ‘mollycoddling’ and calling in parents. At secondary level, self harm was disturbing…
School admin, certainly in a small school, is a strange role. I found that other staff (ie TAs) were a little distant, as they viewed me as working closely with senior leaders, but I was being paid the same as them and had less of a defined role. I never got a lunch break. Although by law I was entitled to one, effectively there was never any one to cover me so I sat at my desk eating while the phone was ringing, the gate was buzzing and children were being sent for first aid!
Having read other threads, you will know that the most important thing to be well versed in at interview is safeguarding. Don’t think it won’t happen. Pretty much every day brings a new safeguarding concern and some stuff is heartbreaking. At secondary level, there is some scary 💩.
Being able to communicate well is essential: in person (parents - sometimes abusive - staff, children, other authorities); written (numerous emails to answer and communications to send out); and on the phone. There is a lot of organising (trips, events, activities etc).
There were positives. Many of the children and young people (and parents) were lovely and it was a privilege being a part of their lives - I felt like I was making a (small) difference. I was certainly never bored! I left a few months ago. My palpitations have gone (anxiety caused by the role) and I never intend to return to a school-based job.
Sending best wishes for your interview and making the decision that is right for you.