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Found flights for those dates with Spanair approx 438 euro

I'm getting conflicting information for those dates, depending on which site I use. Some services are showing a flight duration of between 5 and 8 hours, which would perhaps suggest a change at Madrid or Barcelona.

Those dates are Saturdays, and I believe Iberia may have a direct service on Saturdays to Tenerife Los Rodeos which takes just under 3 hours.

I can see a direct service on Sundays and Mondays with Spanair, and a direct service on Tuesdays with Air Europa, all to Tenerife Sur, with a flight duration of 3 hours. I'm not seeing any direct services to Tenerife Sur on Saturdays, but hopefully someone else may come up with something.

David