Have you lost any water though?
Check for air bubbles on the dip stick aswell
Smell the coolant tank too.
Try not to drive it inbetween mate, If the head has gone and it over heats you could do a lot of damadge, Also ask them if they are going to skim the head when they do it.
I'd be inclined to put it down to turbo seals. A blown head gasket on a 72k 1.8T without an underlying overheating problem is pretty much unheard of, in fact a blown head gasket on the 1.8T is almost non existent in any circumstance.