Inset days take place in term time at our local schools.
Last year, schools here were delayed returning to school after the six week holiday due to a teacher training day!
They'd had six bloody weeks to do it, but delayed the start of term instead.
Seems perfectly acceptable to do this, but not take your child out without a fine.
It may not happen in your area, but it certainly happens in mine.
Ok let's try again.
Term time is 190 days.
Teacher contracts (and some support staff) are term time + 5 days = 195 days
The 5 days for training are outside term time. It doesn't matter where those 5 days are in the year, the pupils would not have been in school.
If a school has a training day at the start of the school year (which is common sense) then it doesn't matter whether there's a training day or not because your kids would not have been in school that day.