Satellite-sea-surface-temperature date

Hi,

I am having issues with the date when downloading satellite-sea-surface-temperature using the API in R. For example, when I request to download 2000 May 02, the file name of the data has the correct date in it. However when I check the time variable, it is 610113600. I assume this is epoch time, but perhaps I'm wrong? When converted to regular date time format from epoch it is 1989-05-02 12:00:00 UTC.  I have tried this for several different years (eg 1999, 2009, 2018, etc) and have had the same issue. The day/month are correct but the year is wrong. I also downloaded a file from the toolbox online to double check, and I get the same issue with the time variable. Am I misinterpreting the time variable in the data? 

TIA!