A job can be edited in the Web Portal and the App (depending on the user's permissions).
In the Web Portal > Jobs > Jobs List > Select the Edit pencil > Edit the Job time > Dispatch.
To edit a job in the Scheduler > click the job that you would like to edit > Edit Job > Edit the Job time > Dispatch.
To edit a Job in the App > Jobs > Search for the job you would like to edit > Select Edit > Edit the Job time > Dispatch.
Alternatively, you can also select Re-schedule and change the time/date there.