How to do a campaign based on the day of the week

I would like to do a campaign condition that runs only on certain days of the week. For example if the form was submitted on Sunday it would take a different route then on Monday.

Also I tried to trigger an email to be held until Sunday. I tried to do schedule the email with a relative time period of 0 days and limiting the schedule to only Sunday. But for some reason it was sent immediately. Anybody can explain me how this feature is supposed to work? Is there a bug or is there something I do not understand?