With the new ones, is time spent driving ( in a car ) to collect a truck counted as 'work' or 'rest'. I seem to remember years ago there was a part called 'other work' for such stuff.
A car is a non regulated vehicle and that time is not required to be put into a work diary, example to/from work.
If one was working in the depot, e.g. before/after driving a regulated heavy vehicle (over 12 t gvm & over 100km from base) loading/unloading/fueling/washing and went and got spare parts or part of a load in a vehicle under 12 t gvm this would be work time.
Stay on the one time zone during your entire trip.
Crossing a state boarder one should keep using a diary.
"Bite off more than you can chew and chew like hell."