Can I change my ad account time zone?

Your ad account's time zone is imported from Facebook, and is set the moment the ad account is created. You cannot change the time zone for your ad account in Legacy Hootsuite Ads.

You can change the time zone of your ad account on Facebook, but this deactivates the existing account, stops any of its running ads, and creates a new ad account with the new time zone. You must then import this new ad account into Legacy Hootsuite Ads.