Cooling System Problems Cause Head Gasket Failure on Subaru Impreza Outback

Began smelling the sweet smell of coolant burning as temps have dropped. Traced back to LH head, rear side. Dripping about 1 drop/min after shutting car down (until everything cools and the head-to-crankcase clearances join back up).
This followed after a recent coolant servicing. Application of Subaru Coolant Conditioner as instructed by the WRP-99 seems to have abated the leak for the time being.
Will be replacing head gaskets as soon as funds allow, as 8 yrs/100k miles was aptly chosen and we are now beyond that 8 yr limit!