My kid started to take school bus last Nov when she just reached age 2.
As she did not join the class at beginning of the academic year, the school just allow one adult to accompany her for the first 2 days when go uphill (no accompany when go downhill).
Starting day 3, she was on the bus with herself. Surely she cried and that last for 2 weeks only.
One teacher on the bus said, even in the first 2 weeks, the little girl only cried for a short while (not the entire journey).
After all, she seldom cries when go downhill as she knows she going home.
That's sounds ok! My son will start attending N1 this November too. I will request to accompany him on the schoolbus in the first few days then. Thanks for your sharing! :)