I just did this deal with ATT and got 1200 off the Galaxy S20 Ultra
I opened a new account, ported a number from google voice and traded in my Galaxy S8.
You do have to be in a 30 month contract to receive all the credits.
Is the first phone I get since my S8 so I don't upgrade until I see it necessary. So it may not be good for the people that don't want a contract or want to upgrade every year.
You can also get a Galaxy Tab5e for 5$ a month when you get a new phone with a line of service for 10$ or added it to your unlimited plan for 20$.