Updating Ford Focus satnav

Can someone please tell me how to get an upgrade for my Ford Focus 2014 sat nav? The Ford dealer (who wasn't really much help) says it's now a TomTom product and as Ford is out of stock with a 9 month waiting list (by which time it will be time for another one!), it's best if I get it from TomTom . Unfortunately, the Focus doesn't seem to be one of those models on the TomTom list of cars, so I'm really stumped.