I have worked as a Maths teacher for 2 years full time in a different school in the same group.
I also have a qualification from the UK that this place really look for when employing subject teachers.
Getting a call out the blue to offer me a substitute role and no guarantee of hours, especially when another school in the same network gave me no hours for 3 months straight didn't go down well with me.
I told them they can stop trying to hire me on the cheap and to go do one.
Don't think they'll be trying to get me on a zero hours contract any time soon.