I started FIFA 20 on my PS4 and I found a little banner in the game on the home screen stating that FIFA 21 Standard Edition is now 50% off. After clicking its saying it is now down to £10.79 with a playstation plus membership and is available until 03/03/21. So if you are interested in upgrading have a look on the FIFA 20 game. I hope it's not account specific but it's definitely on mine as per the picture.
Hopefully it works for someone looking to upgrade.