GT20 in Corsica not as shown for a section

We are following the GT20 in Corsica, for which the app has been superb. However, between Cozzano and Zicavo, the signposted route continues to use the D69. The app goes off to the west, following an even more minor road. I have saved the route we were using as ‘GT20 rerouted Corzanno - Zicavo’. Signposting at both ends goes via D69. Maybe it’s been moved?