Depends on the airline, I'm not entirely sure that Frontier has any minimums, none are published on the website. I have 565/66 and got an interview. PenAir requires 700TT for the 121 side, Commercial Multi for the right seat of a Caravan in the bush. I'm also not sure what their hiring projections are for the rest of the year, I'm assuming they'll have a class date scheduled soon as they are still interviewing.