If you are talking about this message: On February 18th, 2020 this styling option will be removed from the D&D 5E by Roll20 character sheet. If you would like to continue using this style you can opt into the legacy character sheet that has been added to a character sheet select. Navigate to your Game Settings and select "Dungeons & Dragons 5th Edition Legacy" from the character sheet drop down menu. That refers to the non-D&D styling option. Basically the difference is one of borders and a few other layout differences. Based on what I can see here, nothing is happening functionally to the sheet, but the option to maintain two different styles is being removed. You'll simply see only the D&D styling after the 14th. If for some reason, the style differences are important enough to some folks, they have the option of switching to a deprecated version, which will not change after that point. My assumption is that current functions will continue to work (Compendium, etc.) but as time goes on, it will become less compatible. Of course, I could be wrong, but that seems the only reasonable interpretation. My guess is that this will allow for a more streamlined development of the sheet, reducing the time consumed by maintaining two separate CSS sheets. Hopefully there will be an official announcement soon.