Dammit, EAC may be an issue on Linux though. It’s kinda hit or miss whether a given developer will take the extra steps, particularly given the conflicting sources on just how complex it actually is. According to Valve, it’s a checkbox and dropping a file in your depot. Others claim it would require an Epic Online Services version of EAC, with all the baggage that carries, including potentially rewriting a whole chunk of your code.
If you don’t pay for late checkout, you can’t check out late. If you don’t pay for the DLC, you can’t play the DLC. You can still check out at the normal time (which is the basic service) or play the base game, respectively.