I encountered the same error in one of my geolocator files. What worked for me was to subset the raw data to make sure the dates don't span more than 1 year. My original data file spanned from 6/15/16 to 8/5/17, and I think having >1 year of raw data is what causes that error to pop up. I subsetted my raw data so it only went from 6/15/16 to 6/14/17 and then the preprocessLight function worked.
In my case I only needed the 1 year, so I didn't lose data that I wanted. I suppose if you wanted to cover the whole span that you have and it's more than 1 year, you might have to do it in two chunks (separate your raw data into two dataframes).
I realize this reply is a year after your original post, but I hope this helps in case this has still been a problem. Or at least it can help other folks looking this error up as I did at first just recently.