Go to Setup - Website Definitions.
In the Configuration Name field, select the website configuration for which you want to define the service start times in dynamic packages.
In the navigation pane, select Content - Services - Dynamic Package.
The Dynamic Package page is displayed.
Scroll down to the General expander.
In the General Definitions section, in the Transfer drop-off at airport <x> hours prior to departure field, enter the amount of time prior to the flight departure that the transfer should drop off passengers at the airport.
Click Save.
Once the changes are saved, the following pop-up message appears (according to the relevant website configuration).
Click OK.