As I stated previously, though there is safety in numbers, it doesn't matter so much when an ambush occurs, night or day. On a main road it's almost unheard of, though I can see why you would worry given the bandits previously. Let me be clear, this is a main road that is well protected by roadmasters and guards patrolling it. There is currently no advisory on it. Triboar trail is a different story and camping in the snow is likely not the best option for the mules, so plan accordingly.
I merely suggest you read the animals' personalities and charm them with kindness and respect. Booping them on the nose will get you about as far as it did with the wyrmling.