This isn't really a question since this might be the expected behavior, but since I spent a good chunk of time pinpointing the problem, figured I'd share.
I was playing around with SEDFs and had some issues plotting a SEDF that had NaT datetime values. The error it gave was
This seems to only be an issue if all the values in a datetime column are NaT. I won't go into details why, but there was a datetime column that didn't have a single valid datetime value, all values were null/NaT.
So, the following line of code was causing the error