Ran into a bug where some code was taking an hour long interval and subtracting 1 year from the start and end times. But the time library handled subtracting a year from Feb 29 as converting it to Feb 28th of the previous year, at the same time. So on-call got alerted because a job failed when an exception was thrown because the start time was after the end time. Fortunately, other than the alert, there wasn't any negative impact. Although, I think if this isn't addressed it may cause issues next year when it includes a bigger interval of time than expected on March 1st.