Perhaps your owners manual reads different than mine, but I don't start the toad at rest stops. My manual says to start it at fuel stops. Really ambiguous as that distance could vary greatly. I have a 150 gal fuel tank so fuel stop could be over 1,000 miles. Since we normally travel 200 - 300 miles then spend a few days, I just start it when we get where we're going, then use it for a few days.
2006 Gulfstream Friendship G7, Cat C7 and Allison 6 spd
Honda VTX and Crusier Lift on the back
Blue Ox Aladdin, Brake Buddy, 2014 Chevy Equinox toad