What are the time units used in the Route Optimization API?
Is the time unit given in seconds
is time “absolute” i.e. specific time in a 24 hour day given in seconds: e.g. 10:30 will be given as 60x60x10,5 =37800
Yes. Basically you define your start time, which is often Monday but could be also the Monday of the previous week to model 2 weeks or Sunday or similar.
What happens when some area goes into daylight savings time? Is this daylights savings time safe?
You specify the time, e.g. earliest_start and time windows. Thus, arrival times at activity locations are always calculated relative to the departure time of your vehicle. If you have routes crossing multiple time zones (which I think is no issue for last mile delivery) then you need to account for this on your end.