They should have their knackers stapled to their seats and told to get on with it.
As far as I’m concerned (and I’m probably biased as their actions directly affect my income)regardless of how many hours they are contracted to work versus how many hours of overtime they work, they are still on an obscene amount of cash for a Spanish worker. The Canaries now have over 30% unemployment, so you can imagine the amount of sympathy the Spanish ATC’s get from the local community here, especially when their actions disrupt what tourism remains in these difficult times, making things even harder to scrape a living for those that remain.
/rant off