1 hour unpressurized looks quite interesting. Safest/best course of actions ?
If the facts are as reported and they usually aren't: by the time the descent is actioned, by the time you have run the checks, communicated with the cabin crew, made PAs to reassure passengers(more then likely in more then one language) and established a plan of action, communicated with the company and allowed extra mileage for a descent rate of 500fpm for the remainder of the flight you will be as near as makes no difference to CRL. May as well continue to destination if no one requires emergency treatment.
I'm sure this thread will descend into total hysterics by uneducated and uninformed muppets because Ryanair has been mentioned. Ho Hum.