So a new hairdresser is saying that he will put bleach foils in my hair first then move onto tint all over in between the foils. He said he would then process it for 45 mins from when he’s finished placing all the colour so he said this would take up to 1 and a half hours as it would take 30 mins to get all the colour on. That would mean that the some of the bleach highlights would be processing for up to an hour and a half which sounds like a very long time for bleach to sit in hair. My hair is already processed and very fine. Does this sound ok? I’m very nervous about damage.