How to potty train when you have to be in the car?

We’ve started potty training my 2-year-old since this weekend was a 3 day weekend. He’s doing fairly well, but is pantless and has a tiny potty in the living room. We are the ones prompting him to sit on it.

During the week, my son has to take long car rides. He spends about an hour in the car daily, picking up my niece from preschool. He goes to dance class, which is 30 min away. He is in the car a lot.

How do I manage this? I’m afraid if I put him in a pull up, he’s going to feel like it’s a diaper and wait until we put it on to pee. However, he also falls asleep on a lot of the car rides. He usually doesn’t pee in his sleep, but I’m still nervous.

How did everyone manage when you could no longer stay at home 24/7?

Side note: we do have a portable potty for the car. But we still have to pull into a parking lot, get him out of the car seat, etc.