update DAG and the

[Jason Chen]

Hi

 I have two questions:

(1) Is it possible to update the DAG ? Say, the task name in the DAG, the
start_date of the DAG and the dependencies of the involved tasks ?

(2) For the airflow UI: "Tree view", it lists the tasks along with the time
highlighted in the top (say, 08:30; 09:00, etc). What's the meaning of
time? It looks not the UTC time of the task was running.  I know in
overall, airflow uses UTC time.

Thanks.
Jason