IMHO, this would depend on why you are defining the time of the full
moon. From a spiritual perspective, personally, the moon is considered
"full" at the astrological time. But, prior to that pinnacle, the moon
is waxing in strength as does the spiritual implications. And of
course, post-pinnacle, the moon in waning.
If on the other hand, you're planning a romantic moonlit picnic, I'd
say you have about 3 nights of best moon light for your romance to
blossom.
sunnydays
Steph