Invalid Date for One Hour Period on Daylight Savings

When trying to convert from a string to a QDateTime, the returned value ends up being invalid for a span of 1 hour between 2 am and 3 am on daylight savings (March 10th 2019). As illustrated below:

QDateTime::fromString("2019-03-10 03:00:00", Qt::ISODate); // ok
QDateTime::fromString("2019-03-10 01:59:59", Qt::ISODate); // ok
QDateTime::fromString("2019-03-10 02:59:59", Qt::ISODate); // QDateTime(Invalid)
QDateTime::fromString("2019-03-10 02:00:00", Qt::ISODate); // QDateTime(Invalid)

I am in the Eastern timezone (Canada). I believe there is a difference between US and Canada of when daylight savings actually starts which might be the cause of the issue. Canada appears to start at 3 am but the US starts at 2 am (Eastern Time) - the exact range of time that is invalid.