You don't really have to start from scratch. Angular 1.* will be around for awhile. It won't simply stop working. Eventually they'll stop adding new features,

You don't really have to start from scratch. Angular 1.* will be around for awhile. It won't simply stop working. Eventually they'll stop adding new features, and eventually they'll stop fixing bugs. I don't know what the timeline is for that but it's far from immediate.