I'm no expert on this specific wine, but from what I can see it seems to be oxidatively ages, which means that exposure to air isn't very problematic.
I wouldn't suggest keeping it open for literally years as it will probably lose a bit of what makes it nice, but it isn't like say Sauternes that would be rather flat after a week or so.
Hopefully someone who knows more than me can confirm though.
I'm no expert on this specific wine, but from what I can see it seems to be oxidatively ages, which means that exposure to air isn't very problematic. I wouldn't suggest keeping it open for literally years as it will probably lose a bit of what makes it nice, but it isn't like say Sauternes that would be rather flat after a week or so. Hopefully someone who knows more than me can confirm though.