Looks like the Greek authorities could do with a lesson from jet2 ops. Rhodes is an island of 125k people with another 80k tourist beds (depending on which site you trust). 17 k people have already been evacuated from their accommodation, so nearly 10%. The first rule of crisis management is to stop making it worse. In this case stop sending people out.
For sure jet2 reservations will have received a lot of calls from worried future holidaymakers so they have made it easy for folks to cancel, I’m sure they have the capacity to absorb those holidaymakers onto other packages. It probably makes economic sense immediately and in the future, ie they looked after their customers by cancelling and rebooking and removed a lot of uncertainty from those worried folks. It also separates them from the vociferously outraged on the news who expect miracles to happen when stuff goes wrong, but still want a holiday for 400 quid.