score:11
Well after some further digging I think I found my answer on the US Embassy website:
Immigration officials are currently limiting the duration of stay to correspond with coverage dates provided by the COVID-19 medical insurance. Tourists are not able to extend their stay while in Costa Rica. Those seeking to extend their stay will be required to exit the country and purchase additional COVID-19 medical insurance prior to reentry.
So if I want to stay for X
days then I need to have a valid health insurance policy for X
days.