Problem is J* and V err on the side of caution. Ash cloud within X miles etc.
Yes it was to the Nth yesterday but forecast less than 40nm from airport.
I'd be frustrated as a pax but I'd also be happy knowing that safety comes first.
A quick search you will see Tiger, SQ, Air Asia, Silk all still Bali bound.
Back to my point when is it ok to disregard safety or a volcanic ash report.
All ok till something flucks up, I wonder I'm a few days time if a few engines may devil some issues.