How to find the opening and closing time for the maintenance windows in an Oracle database

To see the last 7 days of opening/closing time for the maintenance windows, use this query:

SELECT window_name,to_char(start_time,'dd.mm.yyyy hh24:mi:ss') "start time", duration 
FROM dba_autotask_schedule 
ORDER BY start_time desc fetch first 7 rows only;

Example output:

WINDOW_NAME	start time	DURATION
SATURDAY_WINDOW	19.06.2021 06:00:00	+00 20:00:00.000000
FRIDAY_WINDOW	18.06.2021 22:00:00	+00 04:00:00.000000
THURSDAY_WINDOW	17.06.2021 22:00:00	+00 04:00:00.000000
WEDNESDAY_WINDOW	16.06.2021 22:00:00	+00 04:00:00.000000
TUESDAY_WINDOW	15.06.2021 22:00:00	+00 04:00:00.000000
MONDAY_WINDOW	14.06.2021 22:00:00	+00 04:00:00.000000
SUNDAY_WINDOW	13.06.2021 06:00:00	+00 20:00:00.000000