Living in the desert I have a good deal of wine stored for me at various retailers throughout the year, followed by a flurry of shipping in late Nov through early Feb.
Of course with madeira, as long as it soes not get so hot as to raise the cork, a quick shipment in the other months is easily done.
An excellent point Jay and an even better reason to bring the venerable Maderia along as your desert island wine. Even if the cork does raise out a bit, no harm and no foul. It really matters not.