Something very weird is going on with these LH-subsidiary operators and AC. Out of the west, AC shows them way too much, and o:ac routes are not shown. Playing with ITA, there are other options which the powertools will allow to book. But pickings are slim. There are AC-sold 4Y+LH routes that compete against AC+AC routes, and then AC*-FRA-LH routes are not available at all even though they could use the same LH segment inside Europe. One example is YYC-LYS (which is served by a PY+Y 330). But I can find many other examples. The route map YYC to Europe is restricted in very strange ways, and I can understand the same for western cities.