Hi, 

while you did this you look to have broken 6 other routes at the rotonda of which I fixed Linea 507: Chiasso Crocione - Chiasso Stazione => Morbio Inferiore Serfontana. Not looked which direction they flow across or if they are return routes.
With JOSM select the east half of the ring, then select each route in the list to see the west half has breaks in the routes.

ciao