So, first off as a TA let me say I fully recognise how hard the job is of a teacher.
At my school I cover lunch time duties everyday and twice weekly break duties, what I find insulting is we are continually asked to cover teachers duties so they can have a chat and be on their phones for 15 minutes, while we are desperate for the loo and would like a drink ourselves, then expected to go straight into lesson after.
I say this because myself and other TA'S have witnessed this for the last 3 months, and most of last year and heard about it in previous years when we worked in other year groups that "this is what they do".
I did get annoyed today when I was asked to cover again and said "oh I'll go out then because you know" and gestured at the teacher, I had to pop round to class during break and I can confirm they were doing exactly that and then to make matters worse when I did finally get to go to the loo there was a "uhhh" from said class teacher waiting for the loo, who had plenty of time to go but was more interested in checking her instagram.