When Haute Savoie was ceded to Napoleon III's France there was a large degree of sentiment within the ceded region for union with Switzerland. Of course, at the time it suited neither Cavour nor Napoleon to have the area decide what it wanted, but maybe a potential divergence can be arranged.
Alternatively, it has to be noted that this area was demilitarised in 1815, and that this demilitarisation went with Haute Savoie when it was ceded to France. Popular thought is that it was breached by France in WW1, but it doesn't really matter anyway as part of the adjunct to Versailles was to anull the demilitarisation
Grey Wolf