Time of day that your ad runs
I scheduled my ad to start running at 01:00 a.m. and set the geographic area to the USA, expecting that the ad will run when the time is 01:00 in my account's time zone (around 18:00 in the Eastern Time). I activated the ad at about 20:00 local time (13:00 Eastern) but it started to run immediately. Where am I making the mistake?
Re: Time of day that your ad runs
Ad scheduling will basically work according to the time zone settings of your account. So in case you are outside US as an example, you first need to identify the time zone difference and then adjust the campaign schedule accordingly.
You can find more details here:- https://support.google.com/adwords/answer/2404244?hl=en
Let us know if this helps!