Eddie, good thinking. Suppose you did start in Christmas and then you tell them you had a recommendation to re-apply in May 2011 (although that is less than 3 years by my reckoning) they will either say 'come back in May' or come back in 2012, or even say no problem start now.
From their point of view they will never wish to lose a good candidate simply through a bureaucratic system.
However if the docs say 4 years the they may well mean Aug 2012. I see your dilemma.