*What is the maximum operating ceiling of a typical jet?
*Why will a jet not fly this altitude?
*When will a jet be able to fly this altitude?
Generally 41,000'. It can and will fly that high. If an aircraft is certified to fly that high then you can bet every last penny you have that the pressurisation WILL be able to cope with it.
However, I think that you should Google "Coffin Corner", "Stall speed versus altitude" and "Maneuver capability at altitude".
Have a look around and then let us know what YOU think.