UPDATE
Starting Wednesday, January 13th, Costa Rica beaches are open until 6 pm.

Ticotimes article:

https://ticotimes.net/2021/01/12/costa-rica-extends-beaches-hours-until-6-p-m-per-report?fbclid=IwAR3JTkiFohynWUXEoE4ydpXZGAbzJwrQNtf9B7ztIqZfYZKtyr7sQWif8CQ