Using the latest Express (3.2.7.0) and MapUpdater (3.3.3) on a pair of New Zealand new nuvis I get offered different map update versions:
For the nuvi 2797LM I'm offered City Navigator Australia / New Zealand 2015.1
For the nuvi 765 with nuMaps Lifetiime I get offered version 2014.4
Does anyone know why this would be?