Is this a
1) "Anyone on the ground in this area should close their windows and not go out" advisory
2) "Do not fly within this area because your engines may fail" advisory
3) "There might be a tiny bit of ash floating around, but nothing to have any particular impact on aviation" advisory ?
1. This is airborne threat not a fallout ground threat
2. Yes it is a do not fly or else
3. Of course it's a warning for a threat which could have a significant impact on your safe operation. Whether you take it as advisory or not depends on how it is transmitted to you.