Dave A. wrote:

It is only the FSS or DUATS weather report for that time that determines if
you are legally allowed to be flying based on your restrictions, whatever
they may be.

I'd say it's the fact of the actual weather at the time and place that you are
flying that determines whether you are legally allowed to be flying, regardless
of what FSS or DUAT says.

In some kind of legal proceeding, you might use the reports from FSS or DUAT to
substantiate that the weather is/was what you say, but it's the actual weather
conditions that determine whether your flying is legal.

Dave